Question: Is human activity primarily responsible for global climate change?

Global Warming is primarily caused by humans Point 1- There is an undeniable spike in CO2 levels in our atmosphere.To deny this is just simply foolish.In a matter of roughly 50-60 years, Co2 levels have spiked from 280 parts per million to over 400. To put that into perspective, in the past 800,000 years, Co2 levels have fluctuated between 180 ppm to 280 ppm. A change of 100 ppm would usually take 5,000-20,000 years, however, the current spike took a mere 120 years. While Co2 levels have certainly been higher than this previously in the history of the Earth, never before has Earth experienced such a rapid spike in Co2, the current increase is 100 times faster than at the end of the last ice age [2]. Point 2 - There is a human fingerprint on the carbon that we release. Carbon from different sources has different amounts of neutrons (called isotopes), for example, Carbon from the ocean is "0" (normal) while atmospheric carbon tends to be from -5 to -9 (meaning 5-9 neutrons removed). However, carbon from fossil fuels is an even lighter form of carbon; -20 to -35 [1]. Using this information, scientists can accurately identify the source of carbon that we find in our atmosphere. It is not coincidental that there’s a rapid spike in Co2 while humans are polluting the air with tons upon tons of fossil fuels, the problem with this is, unlike plants and the ocean, factories don’t take Co2 “back in”. The natural cycle balances the Co2 level by constantly adding and removing Co2, while humans are simply just adding Co2 without removing any [3] as shown by this chart. Point 3 - Using computers, scientists have shown that natural factors simply can't account for the changes we have seen. As shown by the following charts, without accounting human activity, these simulations can’t explain the data we have been receiving. Point 4 - Since Co2 is inevitably a greenhouse gas, such a rapid spike in Co2 will cause temperature changes throughout the Earth. These temperature changes can provide a variety of consequences that scientists and the general population have observed; from rising surface temperatures to rising sea levels to the boundary between the troposphere and the stratosphere shifting up in recent decades. I won't go to the trouble to prove each of what has been observed for this debate is not about whether or not climate change is real, but whether or not it is caused by humans; both Pro and Con agree that climate change is real.In conclusion, scientists have recorded one of the biggest Co2 spikes in Earth history. Using the fingerprints that come with burning fossil fuels, scientists are able to record how much of the Earth's atmospheric carbon comes from the burning of fossil fuels. While the carbon cycle creates more carbon than factories, the carbon cycle is just that... a cycle, meaning it's constantly balancing the concentration of Co2 in Earth's atmosphere. However, factories, cars, and humans as a whole are just adding carbon to the Earth's atmosphere without ever using atmospheric carbon like the carbon cycle does. On top of that, recent computer simulations have shown that in order to get the type of changes we are currently experiencing... human activity has to be included or else the data we get back is not the one we have observed. The absence of human activity in these simulations results in completely wrong data, while the presence of human activity brings back accurate data; meaning human activity plays a large role in the climate of the earth. Since Co2 is proven to be a greenhouse gas and is proven to be directly correlated with temperature (as Co2 goes up so does temperature), a rapid spike in Co2 means rising temperatures across the globe, leading to a variety of consequences that we have recently observed. If not dealt with, these problems can only escalate and cause severe problems/destruction. Links[1] http://www.ucsusa.org......[2] http://globalwarming-facts.info......[3] https://www.skepticalscience.com......

That Humans Are Causing Climate Change Main point - Every major science academy in the west supports it, 97%-98% of scientist support it. 1. 75% of the 20th century increase in the atmospheric greenhouse gas CO2 is directly caused by human actions like burning fossil fuels. CO2 levels were 389ppm (parts per million) as of Apr. 2010 - the highest they have been in the past 650,000 years. This increase in CO2 was a substantial contributor to the 1"F to 1.4"F warming over the 20th century. 2. Human-produced CO2 is warming the earth, not natural CO2 released from the ocean and other "carbon sinks." CO2 from fossil fuel combustion has a specific isotopic ratio that is different from CO2 released by natural "carbon sinks." 20th century measurements of CO2 isotope ratios in the atmosphere confirm that the rise results from human activities, not natural processes. 3. Human produced greenhouse gases will continue to accumulate in the atmosphere causing climate change because the earth's forests, oceans, and other "carbon sinks" cannot adequately absorb them all. As of 2009, these carbon sinks were only absorbing about 50% of human-produced CO2. The other 50% is accumulating in the atmosphere. 4. Human greenhouse gas emissions, not changes in the sun's radiation, are causing global climate change. Measurements in the upper atmosphere from 1979 - 2009, show the sun's energy has gone up and down in cycles, with no net increase. While warming is occurring in the troposphere (lower atmosphere), the stratosphere (upper atmosphere) is cooling. If the sun was driving the temperature change there would be warming in the stratosphere also, not cooling. 5. Computer models show that increased levels of human produced greenhouse gases will cause global warming and other climate changes. Although these climate models are uncertain about how much future warming will occur and how it will affect the climate, they all agree that, to some degree, these changes will happen. The reality of climate change is not contradicted by this uncertainty. 6. Although the amount of human-produced greenhouse gases may seem small to some people, their warming potential is amplified by the water vapor positive feedback loop , allowing them to cause significant warming and climate change. As greenhouse gases heat the planet, increased humidity (water vapor in the atmosphere) results. Since water vapor is itself a greenhouse gas, it can double the warming effect of greenhouse gases such as CO2. 7. Human greenhouse gas emissions are heating the planet, and climate models consistently show that this warming causes an increase in the frequency and intensity of tropical cyclones. The fact that 1975-1989 had 171 category 4 and 5 hurricanes while 1990-2004 had 269 [51] of them (a 57% increase) validates these climate models and the reality of human-induced climate change. 8. Human-produced CO2 is changing the climate of the world's oceans. As excess CO2 is absorbed, oceanic acidity levels increase. Oceans have absorbed 48% of the total CO2 released by human activities and acidity levels are 25-30% higher than prior to human fossil fuel use. 9. An 8" rise in the ocean level has occured (1961-2003) due to human-induced global warming. Global sea levels rose an average of 1.8 mm (.07 in) per year between 1961 and 2003 and at an average rate of about 3.1 mm (.1 in) per year from 1993 to 2003. [3] This sea level rise is the result of warming waters and the melting of glaciers, ice caps, and polar ice sheets. From 1870-2004, a "significant acceleration" of sea-level rise occured, an important confirmation of climate change models. 10. Warming caused by human-produced greenhouse gases is changing the earth's hydrologic climate. Rainfall is increasing in many areas due to increased evaporation stemming from global warming. Higher temperatures are also causing some mountainous areas to receive rain rather than snow. According to researchers at the Scripps Institution of Oceanography, up to 60% of the changes in river flow, winter air temperature, and snow pack in the western US (1950-1999) were human-induced. 11. Warming caused by human-produced greenhouse gases is changing the rate of glacial melt and altering the local climate of many regions. Since 1850, records show a "strong increase" in the rate of glacial retreat. From 1961-2004 glaciers retreated about .5mm per year in sea level equivalent. According to the World Glacier Monitoring Service, since 1980, glaciers worldwide have lost nearly 40 feet (12 meters) in average thickness (measured in average mass balance in water equivalent). 12. Warming caused by human-produced greenhouse gases and soot (black carbon) produced from burning of fossil fuels and deforestation, is reducing the size of the Arctic ice cap. A smaller ice cap reflects less of the sun's energy away from the earth. This energy is absorbed instead, causing air and water temperatures to rise. From 1953"2006, Arctic sea ice declined 7.8% per decade. Between 1979 and 2006, the decline was 9.1% each decade. Climate models predict that Arctic sea ice will continue to retreat through the 21st century further disrupting the global climate. [15] 13. Many organizations believe that human activity is a substantial cause of global climate change. These groups include: the World Meteorological Organization (WMO), the Intergovernmental Panel on Climate Change (IPCC), the InterAcademy Council, the Network of African Science Academies, the European Science Foundation (ESF), the European Space Agency (ESA), the Royal Society (UK national academy of science), the US National Academies of Science, the National Aeronautics and Space Administration (NASA), the National Oceanic and Atmospheric Administration (NOAA), and the US Environmental Protection Agency (EPA). 14. Nearly all climate change studies show humans as the main cause, and studies which contradict this claim are often funded by petroleum companies, making their conclusions suspect given the obvious conflict of interest. From 2004-2005, ExxonMobil gave $2.2 million in grants for climate change research to organizations that deny human caused climate change. In 2006 US Senators Olympia Snowe (R-ME), and Jay Rockefeller (D-WV) chastised ExxonMobil for providing more than $19 million in funding to over 29 "climate change denial front groups."

Humanity is the main cause of global warming. I will restate, than in order to establish that the primary cause of global warming is human activity, it is necessary to quantify the amount and effect (not qualify). No scientist or scientific body to date, to my knowledge, has been able to do so. Specifically, anyone making the assertion that humans are the primary cause of global warming must scientifically establish/prove what percentage is human as compare to natural variability and natural causes. It is not good enough to use terms such as "significant" and "substantially" as they are extremely vague inconclusive terms. An even worse approach is to take the line of reasoning presented on the timeforchange.org site referenced by my opponent, which virtually ignores the question/possibility of natural factors. I will reference the following chart by Climatologist Cliff Harris and Meteorologist Randy Mann to illustrate my position: http://www.longrangeweather.com... Note that on this chart there have been two periods with higher and more prolonged global warming periods in 1100 BC and 1300 AD (up to two-fold greater). My opponent also dismissed the importance of the naturally occurring little ice-age, yet its effect was over three-fold greater than our so called current "human" caused warming period. Being that natural causes are scientifically established to have created global temperature swings 3 times larger, and hundreds of years longer in duration than our current warming period (as recent as 1600 - 1800 AD), it is complete pseudo-science to claim that natural cycles play an insignificant role in global temperature change. In fact, being that we are presently in a period where we would naturally expect to see a warming period in the natural global temperature cycle, one would expect that human activity would have created the largest warming event in the last 5000 years. The chart/link I presented establishes that this kind of warming simply hasn't happened. The evidence I presented could even be used as an argument that Mankind's impact on global warming is negligible as compared to natural variability. Lastly, I acknowledge that my sources attribute a portion of climate change to human activity, but again, "significant" and "substantially" is not a quantification as I asserted earlier. I would ask that my opponent reference scholarly material that definitively establishes that human activity outweighs all other possible natural elements and variables in global climate change.

Is Human Activity an addition to increased Global Warming/Climate Change Throughout Humanity's Existence the species has done nothing but destroyed everything around it. We have seen the extinction of more species at fault of Humanity, we have seen the rising of sea levels and the drying up of rivers and lakes due to Human Activity. This is why I stand in Pro position that human activity is an addition to increased Global Warming/ Climate Change. 1. Humans have increased Climate Change because of Increased C02 emissions Source: Climate Change Causes: A Blanket around the Earth." Climate Change: Vital Signs of the Planet. NASA, 11 Feb. 2016. Web. 12 Feb. 2016. Carbon dioxide is released through natural processes such as respiration and volcano eruptions and through human activities such as deforestation, land use changes, and burning fossil fuels. Humans have increased atmospheric CO2 concentration by a third since the Industrial Revolution began. According to the EPA Carbon Dioxide, which includes fossil fuels and industrial processes, contributes 65% of Global greenhouse gases. The Electricity and Heat production industry emits 25% of Carbon Dioxide. This shows how much Co2 contributes to pollution. Emissions released now will continue to warm the climate in the future. The EPA predicts that climate change will cause the demand for water to increase while the supply of water shrinks. Water is not only essential to human health but also to manufacturing processes and the production of energy and food. Climate change is expected to increase rainfall, thereby causing an increase sediments and in the pollutants washed into drinking water Rising sea levels will cause saltwater to infiltrate some freshwater systems, increasing the need for desalination and drinking water treatment.

Climate Change is caused by Humans Point 1- There is an undeniable spike in CO2 levels in our atmosphere. To deny this is just simply foolish.In a matter of roughly 50-60 years, Co2 levels have spiked from 280 parts per million to over 400. To put that into perspective, in the past 800,000 years, Co2 levels have fluctuated between 180 ppm to 280 ppm. A change of 100 ppm would usually take 5,000-20,000 years, however, the current spike took a mere 120 years. While Co2 levels have certainly been higher than this previously in the history of the Earth, never before has Earth experienced such a rapid spike in Co2, the current increase is 100 times faster than at the end of the last ice age [2]. Point 2 - There is a human fingerprint on the carbon that we release. Carbon from different sources has different amounts of neutrons (called isotopes), for example, Carbon from the ocean is "0" (normal) while atmospheric carbon tends to be from -5 to -9 (meaning 5-9 neutrons removed). However, carbon from fossil fuels is an even lighter form of carbon; -20 to -35 [1]. Using this information, scientists can accurately identify the source of carbon that we find in our atmosphere. It is not coincidental that there’s a rapid spike in Co2 while humans are polluting the air with tons upon tons of fossil fuels, the problem with this is, unlike plants and the ocean, factories don’t take Co2 “back in”. The natural cycle balances the Co2 level by constantly adding and removing Co2, while humans are simply just adding Co2 without removing any [3] as shown by this chart. Point 3 - Using computers, scientists have shown that natural factors simply can't account for the changes we have seen. As shown by the following charts, without accounting human activity, these simulations can’t explain the data we have been receiving. Point 4 - Since Co2 is inevitably a greenhouse gas, such a rapid spike in Co2 will cause temperature changes throughout the Earth. These temperature changes can provide a variety of consequences that scientists and the general population have observed; from rising surface temperatures to rising sea levels to the boundary between the troposphere and the stratosphere shifting up in recent decades. I won't go to the trouble to prove each of what has been observed for this debate is not about whether or not climate change is real, but whether or not it is caused by humans; both Pro and Con agree that climate change is real. In conclusion, scientists have recorded one of the biggest Co2 spikes in Earth history. Using the fingerprints that come with burning fossil fuels, scientists are able to record how much of the Earth's atmospheric carbon comes from the burning of fossil fuels. While the carbon cycle creates more carbon than factories, the carbon cycle is just that... a cycle, meaning it's constantly balancing the concentration of Co2 in Earth's atmosphere. However, factories, cars, and humans as a whole are just adding carbon to the Earth's atmosphere without ever using atmospheric carbon like the carbon cycle does. On top of that, recent computer simulations have shown that in order to get the type of changes we are currently experiencing... human activity has to be included or else the data we get back is not the one we have observed. The absence of human activity in these simulations results in completely wrong data, while the presence of human activity brings back accurate data; meaning human activity plays a large role in the climate of the earth. Since Co2 is proven to be a greenhouse gas and is proven to be directly correlated with temperature (as Co2 goes up so does temperature), a rapid spike in Co2 means rising temperatures across the globe, leading to a variety of consequences that we have recently observed. If not dealt with, these problems can only escalate and cause severe problems/destruction.Links[1] http://www.ucsusa.org...[2] http://globalwarming-facts.info...[3] https://www.skepticalscience.com...

Official May Tournament Final: Global Warming C1) Positive feedbacks dominate climate Carbon dioxide has a significant influence on global land-sea mean temperature. All scientists agree that CO2 has some direct effect, increasing temperature by 1.1 degrees Celsius per doubling of CO2 concentration in the atmosphere. David Evans argues, “Most serious skeptical scientists have always agreed with the government climate scientists about the direct effect of CO2. The argument is entirely about the feedbacks.” [1] Climate sensitivity is the key point in all of climate science. The term ‘climate sensitivity’ refers to -- in this context -- the rise in equilibrium global land-sea mean temperature per doubling of the concentration of carbon dioxide in the atmosphere [2]. A 2005 study by Nir Joseph Shaviv confirms that the climate sensitivity, without any amplification, is 1.1 degrees Celsius [3]. Most serious scientists agree. The argument, as Evans argues, is about the feedbacks. What is a feedback? A feedback is a climate process that amplifies or dampens the effect of a climate forcing. A climate forcing is any factor that influences temperature increase, in this case referring to CO2. So, a feedback is anything that amplifies or dampens the effect of CO2 on climate. Feedbacks that amplify it are called positive feedbacks, while those that dampen it are negative ones [4]. I argue that positive feedbacks dominate climate, and therefore, increase the overall effect of CO2 on temperature. Various studies report positive feedbacks as more likely. Soden and Held report a 2 degree celsius climate sensitivity due to positive feedbacks. The study reports very few negative feedbacks. “Water vapor is found to provide the largest positive feedback in all models and its strength is consistent with that expected from constant relative humidity changes in the water vapor mixing ratio. The feedbacks from clouds and surface albedo are also found to be positive in all models, while the only stabilizing (negative) feedback comes from the temperature response.” [5] A 2003 study by Colman reports a feedback of nearly 3 degrees celsius, and the paper is cited by Soden and Held. In the study, “[a] comparison is performed for water vapour, cloud, albedo and lapse rate feedbacks taken from published results of ‘offline’ feedback calculations for general circulation models (GCMs) with mixed layer oceans performing 2 x CO2 and solar perturbation experiments.” [6] There is much evidence outside climate models as well. Wigley, et al. report a possible sensitivity of greater than 4.5 degrees celsius due to volcanic forcings, and supports an average sensitivity of 3.5 degrees. The study says, “After the maximum cooling for low-latitude eruptions, the temperature relaxes back toward the initial state with an e-folding time of 29–43 months for sensitivities of 1–4 degrees C equilibrium warming for CO2 doubling.” [7] A 2005 study by Forster and Gregory also uses volcanic forcings and feedbacks, and finds a climate sensitivity range of 1 - 4.1 degrees Celsius [8]. Even in a hypothetical scenario where negative feedbacks cancel out positive feedbacks to a climate sensitivity of 1 degree C, research by Ziskin and Shaviv (2011) has predicted that “the largest contribution to the 20th century warming comes from anthropogenic sources.” [9] They find that of the ~0.7 degree C temperature rise in the 20th century (some estimates slightly higher), about 0.4 degrees of that are due to anthropogenic forgings, or about 57% of the warming. Nonetheless, climate sensitivity is likely much higher than that. Research by Patrick Michaels, a CATO scholar, found that the amplifier was 1.6 degrees C [10]. This means that human activity causing global warming is much greater than 57%, even under these low estimates. I still maintain that sensitivity is somewhere around 2 - 3 degrees C. A study by leading climatologist JD Annan -- using the Bayesian statistical approach -- found a mean sensitivity of 3 degrees Celsius [11]. The following graph describes the consensus in the literature on climate sensitivity [12]. The following picture portrays the evidence regarding climate sensitivity. As such, I conclude that the effect of the rise in CO2 on climate is huge. C2) Evidence from paleoclimatology The paleoclimatological record is clear that CO2 has become the chief climate forcing in the Cenozoic Era (which began after the Cretaceous mass-extinction event 65.5 million years ago). Overall, solar activity has increased by 40% in this period. James E. Hansen and Makiko Sato argue, “The sun’s brightness increased steadily through the Cenozoic, by about 0.4 percent according to solar physics models (Sackmann et al., 1993). Because Earth absorbs about 240 W/m^2 of solar energy, that brightness increase is a forcing of about 1 W/m^2 . This small linear increase of forcing, by itself, would have caused a modest global warming through the Cenozoic Era.” [13] It’s clear that “CO2 was the dominant forcing in the Cenozoic.” [13] The temperature changes correspond to the changes in CO2 levels. Take the example of the Vostok ice cores. A study by French and Russian institutes says, “There is a close correlation between Antarctic temperature and atmospheric concentrations of CO2 (Barnola et al. 1987). The extension of the Vostok CO2 record shows that the main trends of CO2 are similar for each glacial cycle. Major transitions from the lowest to the highest values are associated with glacial-interglacial transitions. During these transitions, the atmospheric concentrations of CO2 rises from 180 to 280-300 ppmv (Petit et al. 1999). The extension of the Vostok CO2 record shows the present-day levels of CO2 are unprecedented during the past 420 kyr.” [14] This graph shows the correlations between CO2 and temperature over the past 200,000 years. There is proof that it is warmer now than since the Medieval Warm Period. In fact, it is warmer now than any year since 1400 [15]. Another study that replicated previous ‘hockey stick’ studies shows the following data [16]. Thus, paleoclimatology confirms that CO2 influences climate at huge levels. C3) Human activity I have now established that CO2 is responsible for much more that 57% of global warming, somewhere around 75%. Now, I must establish that humans are responsible for much of CO2 generation. First, a simple correlation -- CO2 levels rose with the beginning of industrial activity [17]. The following graph shows CO2 concentrations over the last 10,000 years. If the ratio between C-14 and C-12 decline, the observation would virtually confirm that human activity is responsible for increase in CO2 concentration. This is because the CO2 emissions humans make come from fossil fuels [18]. This has been observed [19]. Thus, human activity has influenced CO2 decline and CO2 is a driving force of climate. Therefore, I affirm. 1. https://mises.org... 2. http://www.pik-potsdam.de... 3. http://onlinelibrary.wiley.com... 4. http://www.ipcc.ch... 5. http://www.gfdl.noaa.gov... 6. http://link.springer.com... 7. http://onlinelibrary.wiley.com... 8. http://homepages.see.leeds.ac.uk... 9. http://www.phys.huji.ac.il... 10. http://www.int-res.com... 11. http://www.jamstec.go.jp... 12. http://www.skepticalscience.com... 13. http://www.columbia.edu... 14. http://cdiac.ornl.gov... 15. http://www.atmosp.physics.utoronto.ca... 16. http://www.skepticalscience.com... 17. http://www.skepticalscience.com... 18. http://www.skepticalscience.com... 19. http://www.bgc.mpg.de...

Anthropogenic Global Warming I thank 101 for accepting!ARGUMENTSC1. Climate Sensitivity and FeedbacksCarbon dioxide has a significant influence on global land-sea mean temperature. All scientists agree that CO2 has some direct effect, increasing temperature by 1.1 degrees Celsius per doubling of CO2 concentration in the atmosphere. David Evans argues, "Most serious skeptical scientists have always agreed with government climate scientists about the effect of CO2. The argument is about the feedbacks." [1]Climate sensitivity is the key point in all of climate science. It refers to, in this context, the rise in equilibrium global land-sea mean temperature per doubling of the concentration of carbon dioxide in the atmosphere. A 2005 study by Nir Joseph Shaviv confirms that the climate sensitivity, without any amplification, is 1.1 degrees Celsius. [2] The debate is about the feedbacks. What is a feedback? A feedback is a climate process that amplifies or dampens the effect of a climate forcing. A climate forcing is any factor that influences temperature increase, in this case referring to CO2. So, a feedback is anything that amplifies or dampens the effect of CO2 on climate. Feedbacks that amplify it are called positive feedbacks, while those that dampen it are negative ones. [3] I argue that positive feedbacks dominate climate, and therefore, increase the overall effect of CO2 on temperature. Various studies report positive feedbacks as more likely. Soden and Held report a 2 degree celsius climate sensitivity due to positive feedbacks. The study reports very few negative feedbacks. "Water vapor is found to provide the largest positive feedback in all models and its strength is consistent with that expected from constant relative humidity changes in the water vapor mixing ratio. The feedbacks from clouds and surface albedo are also found to be positive in all models, while the only stabilizing (negative) feedback comes from the temperature response." [4] A 2003 study by Colman reports a feedback of nearly 3 degrees celsius, and the paper is cited by Soden and Held. In the study, a "comparison is performed for water vapour, cloud, albedo and lapse rate feedbacks taken from published results of 'offline' feedback calculations for general circulation models (GCMs) with mixed layer oceans performing 2 x CO2 and solar perturbation experiments." [5] There is much evidence outside climate models as well. Wigley, et al. report a possible sensitivity of greater than 4.5 degrees celsius due to volcanic forcings, and supports an average sensitivity of 3.5 degrees. The study says, "After the maximum cooling for low-latitude eruptions, the temperature relaxes back toward the initial state with an e-folding time of 29–43 months for sensitivities of 1–4 degrees C equilibrium warming for CO2 doubling." [6] A 2005 study by Forster and Gregory also uses volcanic forcings and feedbacks, and finds a climate sensitivity range of 1 - 4.1 degrees Celsius. [7] Even in a hypothetical scenario where negative feedbacks cancel out positive feedbacks to a climate sensitivity of 1 degree C, research by Ziskin and Shaviv (2011) has predicted that "the largest contribution to the 20th century warming comes from anthropogenic sources." [8] They find that of the ~0.7 degree C temperature rise in the 20th century (some estimates slightly higher), about 0.4 degrees of that are due to anthropogenic forgings, or about 57% of the warming. Nonetheless, climate sensitivity is likely much higher than that. Research by Patrick Michaels, a CATO scholar, found that the amplifier was 1.6 degrees C. [9] This means that human activity causing global warming is much greater than 57%, even under these low estimates. I still maintain that sensitivity is somewhere around 2 - 3 degrees C. A study by leading climatologist JD Annan -- using the Bayesian statistical approach -- found a mean sensitivity of 3 degrees Celsius. [10] The following graph displays the literature on carbon dioxide sensitivity. The following picture portrays the evidence regarding climate sensitivity. As such, I conclude that the effect of the rise in CO2 on climate is huge.C2. Paleoclimate The paleoclimatological record is clear that CO2 has become the chief climate forcing in the Cenozoic Era (which began after the Cretaceous mass-extinction event 65.5 million years ago). Overall, solar activity has increased by 40% in this period. James E. Hansen and Makiko Sato argue, "The sun’s brightness increased steadily through the Cenozoic, by about 0.4 percent according to solar physics models (Sackmann et al., 1993). Because Earth absorbs about 240 W/m^2 of solar energy, that brightness increase is a forcing of about 1 W/m^2 . This small linear increase of forcing, by itself, would have caused a modest global warming through the Cenozoic Era...CO2 [has been] the dominant forcing in the Cenozoic." [11] The below graph depicts the correlations between CO2 and temperatures over the past 200,000 years. The temperature changes correspond to the changes in CO2 levels. Take the example of the Vostok ice cores. A study by French and Russian institutes says, "There is a close correlation between Antarctic temperature and atmospheric concentrations of CO2 (Barnola et al. 1987). The extension of the Vostok CO2 record shows that the main trends of CO2 are similar for each glacial cycle. Major transitions from the lowest to the highest values are associated with glacial-interglacial transitions. During these transitions, the atmospheric concentrations of CO2 rises from 180 to 280-300 ppmv (Petit et al. 1999). The extension of the Vostok CO2 record shows the present-day levels of CO2 are unprecedented during the past 420 kyr." [12] There is proof that it is warmer now than since the Medieval Warm Period. In fact, it is warmer now than any year since 1400. Thus, paleoclimatology confirms that CO2 influences climate at huge levels.C3. Human ActivityI have now established that CO2 is responsible for much more that 57% of global warming, somewhere around 65%. Now, I must establish that humans are responsible for much of CO2 generation. First, a simple correlation -- CO2 levels rose with the beginning of industrial activity. [13] If the ratio between C-14 and C-12 decline, the observation would virtually confirm that human activity is responsible for increase in CO2 concentration. This is because the CO2 emissions humans make come from fossil fuels. This has been observed. [14, 15] UNDERVIEWI have shown the following:a. Climate sensitivity is likely high, and positive feedbacks dominate climate, suggesting that carbon dioxide can significantly influence global land-sea mean and atmopsheric temperatures. b. The paleoclimatological record demonstrates that carbon dioxide has been the most major climate forcing in the Cenozoic Era, which began 65.5 million years ago. c. Human activity is the main driving force behind rise in CO2 concentrations, and there is (1) a documented rise in CO2 concentrations, and (2) a correlation between carbon dioxide and temperature records. SOURCES 1 - https://mises.org...2 - http://bit.ly...3 - http://bit.ly...4 - http://1.usa.gov...5 - http://bit.ly...6 - http://bit.ly...7 - http://bit.ly...8 - http://bit.ly...9 - http://bit.ly...10 - http://bit.ly...11 - http://bit.ly...12 - http://cdiac.ornl.gov...13 - http://bit.ly...14 - http://bit.ly...15 - http://bit.ly...Thus, I affirm. Over to Con!

Human activities are the main cause global warming. First off, I'd like to thank my opponent for joining this debate and wish them best of luck to them now to clarify a few definitions: (merriam-webster) human- of, relating to, or characteristic of humans activities- the quality or state of being active (in this case, pollution and burning of fossil fuels) main- primary cause- a reason for an action or condition global warming- an increase in the earth's atmospheric and oceanic temperatures widely predicted to occur due to an increase in the greenhouse effect resulting especially from pollution 1.) the earth is heating up because of the dawning ice age a.) About 10,000 years ago, the last Ice Age had come to an end with carbon dioxide levels at an all time low. As the temperature had some drastic changes, rising from about negative 8 degress celcius to about one degree celcius, the carbon dioxide levels continued on its downward slope before slowly rising until recent years when it sky-rocketed. Also, during the last era of warming about 115,000 years ago, the temperature had risen well above what we are experiencing now, yet the carbon dioxide levels were well below the average level ever recorded. Over the past century, the temperature has risen less than half of a degree even though the carbon dioxide levels are nearly twice the highest amount that have been recorded. b.) "Within the 90,000-year Ice Age cycles, the Earth also experiences 1,500-year warming-cooling cycles. The current warming began about 1850 and will possibly continue for another 500 years. Their findings are drawn from physical evidence of past climate cycles that have been documented by researchers around the world." (Warming Caused by Natural Cycle, Not Humans.) This is the side of global warming according to Avery and Singer, two scientists studying climate change. Their research was compiled from years of research on tree rings, ice cores, prehistoric villages, fossils, titanium profiles and numerous other sources. 2.) burning fossil fuels only accounts for a small percent of greenhouse gases a.) The burning of fossil fuels by humans is most often the culprit of global warming but in Avery and Singers research they go on to say that the burning of fossil fuels has little effect on global warming and does not speed up the process. In fact, studies show that humans burning fossil fuels actually account for aprox. 18% of greenhouse gases. Other sources are main contributors. These sources are volcanoes, trees, and even cosmic rays from space can greatly increase greenhouse gases. b.) New research involving ice core results allow us to distinguish which came first, temperature change or change in CO2 levels. Scientists from an organization called icecap concluded that temperature change actually preceded change in CO2 levels by over 800 years. So in fact, temperature change actually causes CO2 levels to rise and NOT HUMANS.

Global warming (full resolution in debate) I. What is a greenhouse gas? A greenhouse gas is a gas that traps heat in the atmosphere that prevents the head from escaping the earth. [1] There are several gasses that are commonly called "greenhouse gas" such as: [2] Carbon Dioxide (CO2): Carbon dioxide enters the atmosphere through the burning of fossil fuels (oil, natural gas, and coal), solid waste, trees and wood products, and also as a result of other chemical reactions (e. g. , manufacture of cement). Carbon dioxide is also removed from the atmosphere (or “sequestered”) when it is absorbed by plants as part of the biological carbon cycle. Methane (CH4): Methane is emitted during the production and transport of coal, natural gas, and oil. Methane emissions also result from livestock and other agricultural practices and by the decay of organic waste in municipal solid waste landfills. Nitrous Oxide (N2O): Nitrous oxide is emitted during agricultural and industrial activities, as well as during combustion of fossil fuels and solid waste. Fluorinated Gases: Hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride are synthetic, powerful greenhouse gases that are emitted from a variety of industrial processes. Fluorinated gases are sometimes used as substitutes for ozone-depleting substances (i. e. , CFCs, HCFCs, and halons). These gases are typically emitted in smaller quantities, but because they are potent greenhouse gases, they are sometimes referred to as High Global Warming Potential gases (“High GWP gases”). Of all these, CO2 makes up the vast majority of 56% [3] My partner already defined a CO2 emission so I've no need to go into that. II. What does a greenhouse gas do? A greenhosue gas locks in the heat from the sun causing what is known as a greenhouse effect. III. Proof that humans are the main cause of global warming I wanted to establish what a greenhouse gas was and how it worked; however, that is not the resolution. We are wanting to know whether or not humans are the main cause. My contention is that global warming is mainly caused by CO2 emissions via human activities. According to the USCS, we know that humans are the cause of global warming for at least 3 reasons (their words in italics): [4] Human fingerprints on Carbon overoad - When humans burn coal, oil, and gas to generate electricity or drive cars, CO2 is released int o the atmosphere, where it traps heat. A carbon molecule that comes from fossil fules and deforestastion is lighter than the combined signals of those from other sources. Natural changes alone cannot explain the temperature changes we've seen - My partner rightfully points out that there is a natural explanation for some of the temperature changes we have seen. However, nature alone cannot account for such changes. For a computer model to accurately project the future climate, scientists must first ensure that it is accurately reproduces the observed temperature changes. However, when the models include only recorded natural climate drivers (i. e. , the sun's intensity), the models cannot accurately reproduce the observed warming of the previous 50 years. When human-induced climate drivers are also included in the models, then they accurately capture recent temperature increases in the atmosphere and in the oceans. When all the natural and human-induced climate drivers are compared to one another, the dramatic accumulation of carbon from human sources is by far the largest climate change driver over the past half century. Lower-level atmosphere — which contains the carbon load—is expanding. The boundary between the lower atmosphere (troposphere) and the higher atmosphere (stratosphere) has shifted upward in recent decades. See the ozone FAQ for a figure illustrating the layers of the atmosphere. This boundary has likely changed because heat-trapping gases accumulate in the lower atmosphere and that atmospheric layer expands as it heats up (much like warming the air in a balloon). And because less heat is escaping into the higher atmosphere, it is likely cooling. This differential would not occur if the sun was the sole climate driver, as solar changes would warm both atmospheric layers, and certainly would not have warmed one while cooling the other. ConclusionC1: Natural cycles alone cannot account for the climate change that we observe;C2: CO2 is a main cause of Greenhouse Gas within the Atmosphere. C3: Activities that humans do on a regular basis emit CO2 into the atmosphere contributing to greenhouse gas. Resolution affirmed. _____________Sources 1. . http://www.epa.gov...;2. Ibid3. . http://www.epa.gov...;4. . http://www.ucsusa.org...;

Global warming is likely anthropogenic In its simplest form, the argument for anthropogenic climate change goes as follows. 1. The Earth's atmosphere keeps the planet much warmer than it would be without an atmosphere.1 2. The main gases which contribute to this are carbon dioxide, methane and water vapor. Collectively these are called greenhouse gases.2 3. The ability of these gases to act as greenhouse gases can be shown in a laboratory.3 4. The quantity of these greenhouse gases in the atmosphere has increased sharply since the Industrial Revolution, and their concentration continues to do so.4 5. The concentration of these gases has increased as a consequence of human activity.5 6. The temperature of Earth's atmosphere has been increasing and continues to increase.6 7. The increase in global temperature correlates with the increases of greenhouse gases.7, 8 8. The increase in temperature has been caused by the increase in greenhouse gases.9, 10, 11 Many different observations find a distinct human fingerprint on climate change: 1. Humans are currently emitting around 30 billion tonnes of CO2 into the atmosphere every year. Of course, it could be coincidence that CO2 levels are rising so sharply at the same time so let's look at more evidence that we're responsible for the rise in CO2 levels.12 2. When we measure the type of carbon accumulating in the atmosphere, we observe more of the type of carbon that comes from fossil fuels.13 3. This is corroborated by measurements of oxygen in the atmosphere. Oxygen levels are falling in line with the amount of carbon dioxide rising, just as you'd expect from fossil fuel burning which takes oxygen out of the air to create carbon dioxide.13 4. Further independent evidence that humans are raising CO2 levels comes from measurements of carbon found in coral records going back several centuries. These find a recent sharp rise in the type of carbon that comes from fossil fuels.14 5. So we know humans are raising CO2 levels. What's the effect? Satellites measure less heat escaping out to space, at the particular wavelengths that CO2 absorbs heat, thus finding "direct experimental evidence for a significant increase in the Earth's greenhouse effect"15, 16, 17 6. If less heat is escaping to space, where is it going? Back to the Earth's surface. Surface measurements confirm this, observing more downward infrared radiation A closer look at the downward radiation finds more heat returning at CO2 wavelengths, leading to the conclusion that "this experimental data should effectively end the argument by skeptics that no experimental evidence exists for the connection between greenhouse gas increases in the atmosphere and global warming.18, 19, 20 7. If an increased greenhouse effect is causing global warming, we should see certain patterns in the warming. For example, the planet should warm faster at night than during the day. This is indeed being observed.21, 22 8. Another distinctive pattern of greenhouse warming is cooling in the upper atmosphere, otherwise known as the stratosphere. This is exactly what's happening.23 9. With the lower atmosphere (the troposphere) warming and the upper atmosphere (the stratosphere) cooling, another consequence is the boundary between the troposphere and stratosphere, otherwise known as the tropopause, should rise as a consequence of greenhouse warming. This has been observed.24 10. An even higher layer of the atmosphere, the ionosphere, is expected to cool and contract in response to greenhouse warming. This has been observed by satellites.25, 26 Overall, there is reason to believe that humans are the main cause of our recent global warming. 1 http://earthguide.ucsd.edu... 2 http://lwf.ncdc.noaa.gov... 3 http://www.enviroliteracy.org... 4 http://www.eia.doe.gov... 5 http://www.eoearth.org... 6 http://web.archive.org... 7 http://www.desmogblog.com... 8 http://www.realclimate.org... 9 http://magma.nationalgeographic.com... 10 http://www.environmentaldefense.org... 11 http://rationalwiki.org... 12 http://cdiac.ornl.gov... 13 http://www.esrl.noaa.gov... 14 http://www.sciencemag.org... 15 http://www.nature.com... 16 http://spiedl.aip.org... 17 http://www.eumetsat.eu... 18 http://www.agu.org... 19 http://www.agu.org... 20 http://ams.confex.com... 21 http://www.met.sjsu.edu... 22 http://www.knmi.nl... 23 http://www.agu.org... 24 http://www.math.nyu.edu... 25 http://www.ufa.cas.cz... 26 http://www.skepticalscience.com...

Resolved: Human Activity Is a Significant Factor in Global Warming on Planet Earth. I accept.

Resolved: Human Activity Is a Significant Factor in Global Warming on Planet Earth. I accept.

global climate change is human caused Yes it is true that Global Warming cannot be stopped. It is also true that it has recently gone up more in the 20th century then it has before. Why do you think that is if not because of the constant burning of fossil fuels humans burn daily. This lets off too many gases into the atmosphere which causes the green house effect which results in Global Warming. Why don't we define Global Climate Change: Climate change refers to any significant change in measures of climate (such as temperature, precipitation, or wind) lasting for an extended period (decades or longer). Climate change may result from: •Natural factors, such as changes in the sun's intensity or slow changes in the Earth's orbit around the sun •Natural processes within the climate system (e.g. ,changes in ocean circulation) •Human activities that change the atmosphere's composition (e.g., through burning fossil fuels) and the land surface (e.g., deforestation, reforestation, urbanization, desertification) Notice the part where it says "human activities". As you can clearly see, humans are a huge factor in Global Warming.

Human activity is adversely affecting the environment & having a negative impact on humankind Models show that both nature and human activity contribute to the warming of this century, however, when humans are taken out of the mix, the warming trend that would occur does not match the warming that is currently happening. http://www.koshland-science-museum.org... "the main reason for warming is greenhouse gases. These are naturally occurring however in the past 200 years since the industrial revolution greenhouse gases have increased – especially CO2, methane, and nitrous oxide, which come from the burning of fossil fuels, vehicles, agriculture & mining" http://www.wnrmag.com... As mentioned – nature and human activity work hand in hand in global warming. For example, water vapour is the most prevalent greenhouse gas in the atmosphere and is natures way of keeping the earth at a stable temperature, however other greenhouse gases are rising and do contribute to the greenhouse effect. As the planet increases in temperature, more water can be held therefore also increasing the temperature – so nature and human activity work together to raise temperatures one step at a time. http://www.slate.com... As an example of how CO2 and temperature seem to go hand and hand a website is provided http://www.whrc.org... I like how you mention that it is the political argument that climate change is real and science proves that it is false – then why is it that it seems that scientists agree that climate change is real and it is the corporations, lobbyists and politicians who is altering reports from their own "climate scientists". http://www.csmonitor.com... http://www.sciencemag.org... "To gain an understanding of the level of scientific consensus on climate change, a recent study examined every article on climate change published in peer-reviewed scientific journals over a 10-year period. Of the 928 articles on climate change the authors found, not one of them disagreed with the consensus position that climate change is happening or is human-induced. These findings contrast dramatically with the popular media's reporting on climate change. One recent study analyzed coverage of climate change in four influential American newspapers (New York Times, Washington Post, LA Times, and Wall Street Journal) over a 14-year period. It found that more than half of the articles discussing climate change gave equal weight to the scientifically discredited views of the skeptics." -from the David Suzuki website. In case you didn't know, David Suzuki is the Rick Nash/Wayne Gretzky/Bruce Lee/Muhammed Ali of environmental science and causes. It shows that companies such as Exxon Mobil are working with top public relations firms and using many of the same tactics and personnel as those employed by Phillip Morris and RJ Reynolds to dispute the cigarette-cancer link in the 1990s. It shows said personnel admitting the science is bunk. http://www.cbc.ca... The trend of China and India and their increase in manufacturing and gas powered vehicles will exasperate the problems of air pollution. Despite progressive efforts, the global affect of a rapidly heating, changing environment, toxins affected the food chain, the oceans rising. The incomes and economics so many of rely on will change rapidly. The ecosystem we rely on is under threat and I provide the evidence to prove the conspiracy to deny the science. Quite simply there is no peer reviewed science that states human activity does not cause global warming. My opponent show the signs of a Republican fanatic who allows his thinking to be ruled by the economics and politics that is threatened by the science.

Mankind Is the Main Cause of Global Warming Human-Emitted Greenhouse GasesIt is known that CO2 levels are increasing. "In pre-industrial times over the last 10,000 years, CO2 was relatively stable at around 275 to 285 parts per million. Over the last 250 years, atmospheric CO2 levels have increased by about 100 parts per million. " CO2 levels are increasing at a level not seen in at least 500,000 years, if not longer. [1]Here is a graph showing CO2 concentrations over the last 10000 years: [2][3]This excess CO2 traps heat. Satellites measure less heat escaping out to space, at the particular wavelengths that CO2 absorbs heat, thus finding ". .. direct experimental evidence for a significant increase in the Earth's greenhouse effect. " In other words, the Earth is retaining more of the heat that it receives from the sun that it received from before. This excess heat manifests itself through global temperature increases. [4]"If less heat is escaping to space, where is it going? Back to the Earth's surface. Surface measurements confirm this, observing more downward infrared radiation. A closer look at the downward radiation finds moreheat returning at CO2 wavelengths, leadin to the conclusion that '. .. this experimental data should effectively end the argument by skeptics that no experimental evidence exists for the connection between greenhouse gas increases in the atmosphere and global warming. '"[5][6]CO2 correlates with temperature. Consider the Cenozoic era (the last 65 million years). Overall, solar activity increased 0.4% over this period. "Because Earth absorbs about 240 W/m^2 of solar energy, that brightness increase is a forcing of about 1 W/m^2. This small linear increase of forcing, by itself, would have caused a modest global warming through the Cenozoic Era. " The CO2 levels caused a much higher forcing. In contrast, atmospheric CO2 during the Cenozoic changed from at least 1000 ppm in the early Cenozoic to as small as 170 ppm during recent ice ages. The resulting climate forcing, as can be computed accurately for this CO2 range using formulae in Table 1 of Hansen et al. (2000), exceeds 10 W/m^2. It is clear that CO2 was the dominant climate forcing in the Cenozoic. "[7]In fact, the temperature changes correspond to the CO2 changes. ". .. there is a close correlation between Antarctic temperature and atmospheric concentrations of CO2 (Barnola et al. 1987). The extension of the Vostok CO2 record shows that the main trends of CO2 are similar for each glacial cycle. Major transitions from the lowest to the highest values are associated with glacial-interglacial transitions. During these transitions, the atmospheric concentrations of CO2 rises from 180 to 280-300 ppmv (Petit et al. 1999). The extension of the Vostok CO2 record shows the present-day levels of CO2 are unprecedented during the past 420 kyr. "[8]This graph shows the CO2-temperature correlation over the last 700,000 years: Indeed, it would be rather coincidental if the recent rise in global warming happened to start just around the time that humans started to emit large quantities of greenhouse gases. However, there is direct evidence as well, in addition to the already established correlation between temperature and CO2. One piece of evidence is a comparison of warming in the troposphere and stratosphere. Because the CO2 is in the upper troposphere, the troposphere temperature would increase, while the stratospheric temperature would decrease, because there would be less heat reaching the stratosphere. "Computer model estimates of the ‘human influence’ fingerprint are broadly similar to the observed pattern. In sharp contrast, model simulations of internal and total natural variability cannot produce the same sustained, large-scale warming of the troposphere and cooling of the stratosphere. "[9][10]This graph shows this: [5]Another piece of evidence is the frequency of cold days and nights. Because the sun only shines in the day time, is the sun was causing global warming, the days would warm faster than the nights, while if greenhouse gases were causing global warming, this wouldn't be observed. It is the latter's prediction that is observed. "What we observe is a decrease in cold nights greater than the decrease in cold days, and an increase in warm nights greater than the increase in warm days. "[5][11]This can be shown in the below graph: [5]Overall, the evidence shows that human-emitted greenhouse gases are the cause of global warming. CO2, in addition to other gases like methane and nitrous oxide are being emitted by humans in very large amounts, and this is manifesting itself in an increase in the average global temperature. Climate Sensitivity and FeedbacksClimate sensitivity is the amount the temperature would rise if the CO2 concentration were doubled. Obviously, if there's a large climate sensitivity, then increases in CO2 have large effect. It is known that the climate sensitivity is around 1 degree C. However, this can be amplified through feedbacks. Positive ones amplify the sensitivity, while negative ones diminish the sensitivity. The evidence overwhelmingly comes down on the former, that positive feedbacks are happening. Increases in CO2 cause temperature increases, which are amplified by water vapor and the effect on clouds. "Since the radiative effects associated with the buildup of water vapor to near-saturation levels and the subsequent condensation into clouds are far stronger than the equilibrium level of radiative forcing by the non-condensing GHGs, this results in large local fluctuations in temperature about the global equilibrium value. "[12]This can be shown in the below graph: Further, increases in CO2 affect the carbon cycle in this way: Global warming can result in the death of vegetation (due to droughts) and the warming of the ocean. Both of these further reduce the maximum absorption of the Earths carbon cycle, thus resulting in even more CO2 being released into the atmosphere. And with this, CO2 increases even more. In other words, CO2-caused temperature increases are amplified by positive feedbacks and the mechanics of the carbon cycle. So, the positive feedback amplifies the climate sensitivity. How much it is amplified can be determined through study. Using a Bayesian statistical approach, which is “the dominant [method] in the literature”, these findings support the notion of climate sensitivity as maximum 4 degrees C, a mean of 3 degrees C, and likely not lower than 3 degrees. [13]The graph below gives a statistical analysis: [14]The mean is around 3 degrees C. The CO2 that humans emit thus has an effect of 3 degrees C per doubling of CO2. This can be shown by the fact that CO2 concentrations have increased from around 275 ppm to around 400 ppm. This is an increase of around 40%. This should manifest itself with a temperature increase of a little less than 1.5 degrees C. Indeed, temperatures have increased around this amount over the last 150 years. The anthropogenic-forcing climate models thus match observations. [15]In other words, in addition to the direct evidence of how the Earth is warming, the climate models based on a greenhouse gas cause to global warming explain almost perfectly the recent global warming. This is a lot of evidence for a human case to the recent global warming. ConclusionGreenhouse gases cause global warming because of their heat trapping abilities. Humans have been emitting vast amounts of greenhouse gases over the last 150 years, and this shows itself on the CO2 measurements. The atmospheric warming pattern and greater heating at night are evidence that the recent global warming is caused by those human emitted greenhouse gases. These increases are amplified through the water vapor and cloud positive feedbacks and the positive feedback that arises through the climate cycle. The climate sensitivity ends up being around 3 degrees C. Finally, the CO2-temperature record shows that the two correlate with remarkable correlation. SourcesSources in comments.

Mankind Is the Main Cause of Global Warming Human-Emitted Greenhouse GasesIt is known that CO2 levels are increasing. "In pre-industrial times over the last 10,000 years, CO2 was relatively stable at around 275 to 285 parts per million. Over the last 250 years, atmospheric CO2 levels have increased by about 100 parts per million. " CO2 levels are increasing at a level not seen in at least 500,000 years, if not longer. [1]Here is a graph showing CO2 concentrations over the last 10000 years: [2][3]This excess CO2 traps heat. Satellites measure less heat escaping out to space, at the particular wavelengths that CO2 absorbs heat, thus finding ". .. direct experimental evidence for a significant increase in the Earth's greenhouse effect. " In other words, the Earth is retaining more of the heat that it receives from the sun that it received from before. This excess heat manifests itself through global temperature increases. [4]"If less heat is escaping to space, where is it going? Back to the Earth's surface. Surface measurements confirm this, observing more downward infrared radiation. A closer look at the downward radiation finds moreheat returning at CO2 wavelengths, leadin to the conclusion that '. .. this experimental data should effectively end the argument by skeptics that no experimental evidence exists for the connection between greenhouse gas increases in the atmosphere and global warming. '"[5][6]CO2 correlates with temperature. Consider the Cenozoic era (the last 65 million years). Overall, solar activity increased 0.4% over this period. "Because Earth absorbs about 240 W/m^2 of solar energy, that brightness increase is a forcing of about 1 W/m^2. This small linear increase of forcing, by itself, would have caused a modest global warming through the Cenozoic Era. " The CO2 levels caused a much higher forcing. In contrast, atmospheric CO2 during the Cenozoic changed from at least 1000 ppm in the early Cenozoic to as small as 170 ppm during recent ice ages. The resulting climate forcing, as can be computed accurately for this CO2 range using formulae in Table 1 of Hansen et al. (2000), exceeds 10 W/m^2. It is clear that CO2 was the dominant climate forcing in the Cenozoic. "[7]In fact, the temperature changes correspond to the CO2 changes. ". .. there is a close correlation between Antarctic temperature and atmospheric concentrations of CO2 (Barnola et al. 1987). The extension of the Vostok CO2 record shows that the main trends of CO2 are similar for each glacial cycle. Major transitions from the lowest to the highest values are associated with glacial-interglacial transitions. During these transitions, the atmospheric concentrations of CO2 rises from 180 to 280-300 ppmv (Petit et al. 1999). The extension of the Vostok CO2 record shows the present-day levels of CO2 are unprecedented during the past 420 kyr. "[8]This graph shows the CO2-temperature correlation over the last 700,000 years: Indeed, it would be rather coincidental if the recent rise in global warming happened to start just around the time that humans started to emit large quantities of greenhouse gases. However, there is direct evidence as well, in addition to the already established correlation between temperature and CO2. One piece of evidence is a comparison of warming in the troposphere and stratosphere. Because the CO2 is in the upper troposphere, the troposphere temperature would increase, while the stratospheric temperature would decrease, because there would be less heat reaching the stratosphere. "Computer model estimates of the ‘human influence’ fingerprint are broadly similar to the observed pattern. In sharp contrast, model simulations of internal and total natural variability cannot produce the same sustained, large-scale warming of the troposphere and cooling of the stratosphere. "[9][10]This graph shows this: [5]Another piece of evidence is the frequency of cold days and nights. Because the sun only shines in the day time, is the sun was causing global warming, the days would warm faster than the nights, while if greenhouse gases were causing global warming, this wouldn't be observed. It is the latter's prediction that is observed. "What we observe is a decrease in cold nights greater than the decrease in cold days, and an increase in warm nights greater than the increase in warm days. "[5][11]This can be shown in the below graph: [5]Overall, the evidence shows that human-emitted greenhouse gases are the cause of global warming. CO2, in addition to other gases like methane and nitrous oxide are being emitted by humans in very large amounts, and this is manifesting itself in an increase in the average global temperature. Climate Sensitivity and FeedbacksClimate sensitivity is the amount the temperature would rise if the CO2 concentration were doubled. Obviously, if there's a large climate sensitivity, then increases in CO2 have large effect. It is known that the climate sensitivity is around 1 degree C. However, this can be amplified through feedbacks. Positive ones amplify the sensitivity, while negative ones diminish the sensitivity. The evidence overwhelmingly comes down on the former, that positive feedbacks are happening. Increases in CO2 cause temperature increases, which are amplified by water vapor and the effect on clouds. "Since the radiative effects associated with the buildup of water vapor to near-saturation levels and the subsequent condensation into clouds are far stronger than the equilibrium level of radiative forcing by the non-condensing GHGs, this results in large local fluctuations in temperature about the global equilibrium value. "[12]This can be shown in the below graph: Further, increases in CO2 affect the carbon cycle in this way: Global warming can result in the death of vegetation (due to droughts) and the warming of the ocean. Both of these further reduce the maximum absorption of the Earths carbon cycle, thus resulting in even more CO2 being released into the atmosphere. And with this, CO2 increases even more. In other words, CO2-caused temperature increases are amplified by positive feedbacks and the mechanics of the carbon cycle. So, the positive feedback amplifies the climate sensitivity. How much it is amplified can be determined through study. Using a Bayesian statistical approach, which is “the dominant [method] in the literature”, these findings support the notion of climate sensitivity as maximum 4 degrees C, a mean of 3 degrees C, and likely not lower than 3 degrees. [13]The graph below gives a statistical analysis: [14]The mean is around 3 degrees C. The CO2 that humans emit thus has an effect of 3 degrees C per doubling of CO2. This can be shown by the fact that CO2 concentrations have increased from around 275 ppm to around 400 ppm. This is an increase of around 40%. This should manifest itself with a temperature increase of a little less than 1.5 degrees C. Indeed, temperatures have increased around this amount over the last 150 years. The anthropogenic-forcing climate models thus match observations. [15]In other words, in addition to the direct evidence of how the Earth is warming, the climate models based on a greenhouse gas cause to global warming explain almost perfectly the recent global warming. This is a lot of evidence for a human case to the recent global warming. ConclusionGreenhouse gases cause global warming because of their heat trapping abilities. Humans have been emitting vast amounts of greenhouse gases over the last 150 years, and this shows itself on the CO2 measurements. The atmospheric warming pattern and greater heating at night are evidence that the recent global warming is caused by those human emitted greenhouse gases. These increases are amplified through the water vapor and cloud positive feedbacks and the positive feedback that arises through the climate cycle. The climate sensitivity ends up being around 3 degrees C. Finally, the CO2-temperature record shows that the two correlate with remarkable correlation. SourcesSources in comments.

Humanity is the main cause of global warming. The word 'main' as used in the debate heading presents the position that humanity's contribution to global warming is greater in magnitude than any other factor. The definition of 'main' could be explained as: chief or principal in rank, importance, size, etc. Therefore, Pro must prove that the human portion is in fact the largest of factors. Of course, the human portion needn't be greater than 50% of the total effect if there are multiple elements/factors at play. I also agree that it is more than possible that human activities could affect, change or initiate natural processes, but again, that would have to be quantified (what portion of a natural system has been altered by human elements versus natural change). Natural and human effect can be intertwined and extremely complicated, if not impossible to differentiate and separate. This is referred to as the "attribution of recent climate change". I will reference the following scholarly article: https://gfdl.noaa.gov... "Detection and Attribution of Recent Climate Change: A Status Report". The authors make several important conclusions in this comprehensive study: "Greenhouse warming alone is insufficient to explain the observed pattern of climate change." and "The most probable cause of the observed warming is a combination of internally and externally forced natural variability and anthropogenic sources (see also Tett et al. 1999). But given the large model uncertainties and limited data, a reliable weighting of the different factors contributing to the observed climate change cannot currently be given. In short, we cannot attribute, at this time, with a high level of statistical significance, the observed changes in global and large-scale regional climate to anthropogenic forcing alone.". This research contradicts Pro's assertion that human causes are definitively more important than natural ones. In addition, to say that our current warming trend was caused solely by the industrial age based on the chart I presented (in round 3) would be to dismiss the fact that the sharp rebound from the Little Ice Age and commencement of our current warming trend (1600-) was initiated and occurred well before human activity was a relevant factor. I agree with much of the content contained within the two sites referenced by pro, but none of them contains information that establishes that human activity plays a greater role than natural variability. The CO2 now website asserts that "The human impact on climate during this era greatly exceeds that due to known changes in natural processes, such as solar changes and volcanic eruptions." and lists several of the unique contributions and circumstances associated with human activity and greenhouse gasses. It also states that "the radiative forcing from human activities is much more important for current and future climate change than the estimated radiative forcing from changes in natural processes." These are grand statements, but there is no attempt to quantify them unlike the formal research document I presented above (which contradicts these sites). There is also no mention on Pro's sites of the fact that our current warming period was initiated well before the industrial age and human influence by natural forces. Even the IPCC continues to protect its reputation by using vague terms such as "...likely" regarding the position of humanity's "...dominant role in global warming". I acknowledge that we currently are experiencing global warming. For those who lived in 1100 BC and 1300 AD, they also experienced global warming on a larger scale than we do today, even though human activity had little correlation to that warming. Thus, to say that Global Warming is unique to the industrial age is false. It is also very likely that scientists will one day be able to prove/quantify what portion of Human Activity is attributable to global warming. Presently, it is not possible as my opponent acknowledges. This is why no scientist(s) or scientific body has declared a victory on this issue (A quantified attribution of recent climate change). In fact, a very large amount of money and large amount of research continues to be spent on this very issue because it has yet to be proved or resolved. I also agree that the current warming period presented on the on the chart I referenced is abrupt and is likely a reflection of the influence of human activity. Being that this warming period has yet to exceed several recent warming periods in effect and duration, we need more time in order to be able to place our current warming period into the context of other prior larger warming periods. It is simply premature to state definitively that human activity is the main factor in global warming. My statement is reflected in the current feverish rate of research being performed into the Attribution of Recent Climate Change. If a definitive conclusion had been reached, this research would not be needed to such a degree. Keep in mind, that I am not advocating that humanity should not take responsibility towards reducing our greenhouse gas emissions; quite the contrary.

Global Warming is Real and is Manmade! In ROUND 3 I will continue my ROUND 2 response, where I will show the link between carbon dioxide emitted by human activity and the increase in global surface temperatures. In the final ROUND I will go over the effects of climate change caused by global warming.Carbon Dioxide (and Other Green House Gases) are Causing Global Warming and Climate ChangeWith the advent of the industrial revolution, human-induced global warming--through such actions as the burning of fossil fuels and deforestation--has led to an unprecendented increase in CO2 concentrations and other green house gases [1][2]. However, climate scientists overwhelmingly pin the blame of global warming on carbon dioxide because it is the most widely and most abundantly emitted green house gas of human activity [3]. According to the Intergovernmental Panel on Climate Change (IPCC), carbon dioxide and methane are responsible for more than 84% of the warming being inflicted on our planet because of green house gases [3]. The remaining percent of warming can be attributed to green house gases like nitrous oxide and flourinated gases [3]. By itself, the IPCC has affirmed that carbon dioxide is reponsible for 54.7% of the global warming caused by green house gases; that's because it is the most abundantly produced green house gas of human activity and because it has an enormous radiative impact compared to other green house gases when accounting for its abundance in the atmosphere, its indirect heating effects, and because of the CO2 molecule's long lifetime in the atmosphere [3][4]. In fact, only water vapor has a stronger green house gas effect than carbon dioxide in our atmosphere, but unlike CO2 water vapor isn't being emitted naturally by any known source at a large enough scale to be blamed for global warming [4]; water vapor does contribute to global warming, but this is because of a feedback loop caused as other green house gasses in our atmosphere increase in concentration and heat up the Earth's lower atmosphere [5].As the Earth's atmosphere and surface become warmer because of green house gas emissions, this drive's more water vapor to be absorbed into the air, further heating our planet; this water vapor loop is well-understood and contributes to anthropogenic (human induced) global warming [5].However, other green house gases emitted by human activity drive this loop and are primarily responsible for global warming. As the statistic above shows, carbon dioxide is responsible for 54.7% of the warming being inflicted on our planet because of human activity. As I demonstrated with the graph on carbon dioxide concentration in our atmosphere in ROUND 2 (and as I reported in ROUND 1), never in the last 400,000 years has the CO2 concentration been quite so high as it is today! Ice core analysis shows that in the last half-million years the peak concentration (the highest concentration) of CO2 was almost 300 parts per million--and that was 300,000 years ago [1]. Today the concentration of atmospheric CO2 is 398 parts per million! Nearly 33% higher than it has ever been in the last half-million years [1]!This unprecedented increase in atmospheric carbon dioxide can be attributed almost entirely to human activity, such as through large-scale deforestation, land use changes (such as methane emission from ammonia-based fertilizers), and the burning fossil fuels (which include coal and gasoline) [2]. The IPCC reports that in the last 150 years, human activity has increased atmospheric carbon dioxide levels from 280 parts per million to 398 parts per million today [2]! According to the United States Environment Protection Agency (EPA), humans largely emit carbon dioxide and other green house gases from the production of electricity and from transportation; in the U.S. these two behaviors contribute to 60.8% of all the nation's emitted green house gases in a single year [3]. Other behaviors, such as those of industry, businesses, of agricultural, and of energy use in homes, contribute to the remaining 39% of the nation's green house gas emissions [3].Global warming is produced when green house gases in the atmosphere--water vapor, carbon dioxide, methane, nitrous oxide--accumulate in the atmosphere and act as a thermal blanket for the Earth, absorbing the sun's radiative heat and warming the Earth's surface [2]. Nature uses green house gases to facilitate heat trapping from the sun's rays to warm the Earth and make biological life on the planet possible. But if the concentrations of green house gases in the atmosphere become excessive, this can overheat the planet, alter the Earth's climate system, injure natural ecosystems, and make it harder for biological processes to take place and be maintained. This is exactly what's happening now and generating planet-altering climate change (these effects will be explicated in the final ROUND).Volcanes and Changes in the Sun's Solar Output are Not Contributing to Global WarmingSome skeptics claim that erupting land and submarine volcanoes are causing global warming. But reports by the U.S. Geological Survey (USGS) shows that volcanoes primarily emit gases, like sulfur dioxide, at high enough concentrations so as to encourage global cooling [6]. In fact, the USGS takes the position that erupting volcanoes typically emit gases that are more likely to lead to global cooling[6]! The USGS asserts that CO2 emission by human activity dwarfs the output of CO2 by all volcanoes worldwide [6].Some opponents of manmade global warming claim that the Sun's solar output is responsible for the current rise in atmospheric temperatures--that humans are not responsible for the modern warming trend. But this is a view that the scientists firmly dispute, based on a variety of evidence (2):--Scientists point out that, since 1750, the average amount of energy coming from the sun either remained constant or increased only slightly.--If the warming were caused by increased radiation coming from the sun, then scientists would expect to see warmer temperatures in all layers of the atmosphere. Instead what they observe is a cooling in the upper atmosphere, and a warming at the surface and in the lower parts of the atmosphere. Scientists say that this is a strong indication that green house gases are responsible for global warming, because they trap heat in the lower atmosphere.--Computer climate models that include solar irradiance changes can't reproduce the observed temperature trend over the past century or more without including a rise in green house gases.All of these bits evidence demonstrate that solar irradiance is not responsible for the rise in Earth's surface temperatures over the last century or more.Elevations in Atmospheric Carbon Dioxide Concentrations have been responsible for Prehistoric Rises in Global Surface TemperaturesScientists that study prehistoric ice ages and warming ages point out that carbon dioxide released into the atmosphere by geologic activity or other natural events has consistently led to warming trends in Earth's history. For example, the Ice Age that stretched during most of the Cryogenian Period (840 - 635 million years ago) had the potential to cover the entire globe and would have been a major setback for biological life and evolution in general had it been this severe. Scientists that study the period point out that this extreme condition never occured because, as the Earth froze, atmospheric oxygen was forced into the oceans, which oxidized organic matter and released CO2 into the atmosphere, preventing temperatures from falling any lower [7]. Presently scientists have no other plausible model to explain how the atmosphere was able to maintain warmth while the Earth froze [7]. Scientists also point out that a rise in atmospheric CO2 concentrations have led to prehistoric Warming Ages. 55 million years ago, the Earth entered a sudden and rapid global warming event, which scientists call the the Paleocene-Eocene Thermal Maximum (PETM). Analysis firmly demonstrates that the quantity of carbon and carbon dioxide in the atmosphere rose significantly at the beginning of this period [8] [9]. The increasing concentration of CO2 is considered the chief reason why the atmosphere warmed so rapidly during PETM [8] [9]. Ice core analysis also attributes the end of the last ice age to an increase in atmospheric CO2 levels[10].That carbon dioxide is a heat-trapping greenhouse gas is sound; its heat-trapping effects have been studied in laboratories throughout the world. Its contribution to prehistoric global warming has long been understood, even before the concept of man-made global warming entered the imagination [11]. [1] (http://climate.nasa.gov...)[2] (http://climate.nasa.gov...)[3] (http://www.epa.gov...)[4] (http://en.wikipedia.org...)[5] (http://www.nasa.gov...)[6] (http://volcanoes.usgs.gov...)[7] (http://news.softpedia.com...)[8] (http://en.wikipedia.org...)[9] (http://smithsonianscience.org...)[10] (http://www.livescience.com...)[11] (http://en.wikipedia.org...)

Is Human Activity an addition to increased Global Warming/Climate Change Before I begin my argument, let me emphasis that regardless of whether "human activity is an addition to increased Global Warming / Climate Change", people should try their best to act for the common good. With that said, you have not properly defined what "human activity" is and what level of change constitutes "Climate Change". Not all human activities cause Global Warming or Climate Change. Furthermore, your evidence at best, only shows that human expels more CO2 than other species, but never considers whether such level of increase is detrimental. If you do not define what is detrimental, then it can be said that the level of CO2 expel by my hamster is causing Global Warming.

Is Human Activity an addition to increased Global Warming/Climate Change Just for clarification when I say human activity I mean the activity to the addition of climate change, as you could see by the evidence I used. What level of change contributes to climate change would be the rising temperatures. Since that humans release so much C02 and pollute the air it contributes to warming the planet. The EPA predicts in the next 100 years global temperatures will rise by 2 degrees. Now you may say that isn't much but that will cause the melting of the ice caps which will cause rising sea levels which will sink cities, as National Geographic reports. As you said that not all human activities cause Global warming, I acknowledged that in my evidence but as I will state again NASA reports that humans have increased atmospheric C02 emissions by a third since the industrial revolution, and the largest known contribution is fossil fuels, WHICH IS DONE BY HUMANS. My evidence shows more than that humans expel more C02 than any other species, in my evidence you can clearly see that these levels are detrimental. As I said Water shortages, food shortages, Ocean Acidification, the evidence is all there. Also to say I would not have to define detrimental that word is of common knowledge and if you can't accept that I'm sorry you're too incompetent. So I have won this debate because you have not even stated one piece of evidence that goes against my case, and your entire argument is on not defining common knowledge terms so for these reasons this is why Pro as won this debate.

Global warming is mostly anthropogenic I will begin round two by defining a few additional terms: Isotope: One of two or more atoms with the same atomic number that contain different numbers of neutronsInfrared radiation: Electromagnetic radiation which we humans perceive as heatTroposphere: The lowest portion of Earth’s atmosphereClimate forcing: An externally imposed perturbation in the radiative energy budget of Earth’s climate system Now, on with the debate! Carbon dioxide emissions are increasing rapidly. In 1870, the amount of carbon dioxide in the atmosphere was about 290 parts per million (ppm). As of April 2011, the amount of carbon dioxide in the atmosphere had risen to approximately 390 ppm (1). Very carefully calibrated measurements have confirmed that human activities are the primary cause of this increase, as I will demonstrate below. There are two primary carbon isotopes: carbon-12 and carbon-13. Carbon dioxide produced from burring fossil fuels and clearing forests has a unique isotopic composition. This is because plants prefer lighter isotopes, that is they prefer carbon-12 over carbon-13. Fossil fuels like coal or oil are derived from ancient plants. Thus, when we burn fossil fuels, we’re releasing more of the lighter Carbon-12 into the atmosphere. If human activities are the primary cause of the observed increase in carbon dioxide concentrations, we would expect to see the ratio of Carbon-13 to carbon-12 fall. Indeed, this is just what we observe. Measurements from the atmosphere (2), corals (3), and sea sponges (4) indicate that this ratio has declined greatly over the past 100 years. Without a doubt, the rise in atmospheric carbon dioxide is almost entirely anthropogenic. As I will demonstrate, several lines of evidence indicate that the current warming trend is caused by this increase in carbon dioxide. 1) More Infrared radiation is returning to the Earth: If carbon dioxide is responsible for global warming, more infrared radiation should be returning to the surface. Before presenting further evidence which affirms the resolution, I will provide a simple explanation of why this is so. The Earth emits a large amount of infrared radiation into the atmosphere. Some of this heat is absorbed by carbon dioxide molecules, which then reemit infrared radiation in all directions. Some radiation spreads downward and ultimately comes back into contact with the Earth’s surface, where it’s absorbed. However, some of the radiation spreads upward. In the upper layers of the troposphere, carbon dioxide molecules are sparse, and this heat energy can eventually escape to space. When additional carbon dioxide molecules are added to these layers, significantly more thermal infrared radiation from lower levels will be absorbed. Therefore, the place from which heat energy finally leaves the Earth will shift to higher layers. These layers are very cold, since temperatures decline greatly with altitude in the troposphere. Notably, the amount of energy emitted by an object is proportional to its temperature. Thus, these high altitude layers will emit significantly less radiation than the layers below, thereby retaining a large amount of heat energy. As these layers accumulate heat, they will warm and emit an increasing amount of infrared radiation. Thus, more radiation will spread downward and reach the surface, causing the surface to warm as well. Measurements from ground stations indicate that more infrared radiation is indeed returning to the Earth (5-6). When we take a close look at the spectrum of this radiation, we can determine how much each greenhouse gas is contributing to the warming effect. From these results, one scientist concluded that, “This experimental data should effectively end the argument by skeptics that no experimental evidence exists for the connection between greenhouse gas increases in the atmosphere and global warming” (6). 2) The upper atmosphere is cooling: As greenhouse gases trap more heat in the troposphere, less infrared radiation reaches the upper atmosphere, beginning with the stratosphere. Therefore, if the increase in carbon dioxide is responsible for the current warming, we would expect to see cooling in the upper atmosphere. This has been observed by several scientific researchers (7-9). 3) The tropopause has risen: Theoretically, global warming would also lead to an increase in the tropopause height. The tropopause is the atmospheric boundary between the troposphere and the stratosphere. Because the troposphere has warmed and the stratosphere has cooled, the tropopause has risen several hundred meters over the past three decades (10). 4) Oceanic heat content is increasing: Ocean heat content is increasing, especially in the upper layers. This specific pattern of ocean warming, with heat penetrating from the surface, can only be explained by greenhouse gas warming. As Barnett et al. concluded, “[The increase in ocean heat content] cannot be explained by natural internal climate variability or solar and volcanic forcing, but is well simulated by two anthropogenically forced climate models. We conclude that it is of human origin, a conclusion robust to observational sampling and model differences. Changes in advection combine with surface forcing to give the overall warming pattern” (11). 5) Observed precipitation trends can best be explained by increasing carbon dioxide: Zhang et al. showed that models do a much better job of matching the observed precipitation trends when anthropogenic climate forcings were included. As they stated, “Anthropogenic forcing has had a detectable influence on observed changes in average precipitation within latitudinal bands, and that these changes cannot be explained by internal climate variability or natural forcing. We estimate that anthropogenic forcing contributed significantly to observed increases in precipitation in the Northern Hemisphere mid-latitudes, drying in the Northern Hemisphere subtropics and tropics, and moistening in the Southern Hemisphere subtropics and deep tropics. The observed changes, which are larger than estimated from model simulations, may have already had significant effects on ecosystems, agriculture and human health in regions that are sensitive to changes in precipitation” (12). 6) Most scientists believe that global warming is anthropogenic: Several studies have surveyed climate scientists who are actively publishing climate research. All of these studies found that over 97% of climate experts are convinced that humans are the primary factor changing global temperature (13-14). I look forward to my opponent's response! References: http://www.esrl.noaa.gov... http://bluemoon.ucsd.edu... http://www.webpages.uidaho.edu... http://mgg.rsmas.miami.edu... http://www.agu.org... http://ams.confex.com... http://journals.ametsoc.org... http://www.ufa.cas.cz... http://www.agu.org... http://www.math.nyu.edu... http://www.sciencemag.org... http://www.cccma.ec.gc.ca... http://www.pnas.org... http://tigger.uic.edu...

Mankind Is the Main Cause of Global Warming Extend

Mankind Is the Main Cause of Global Warming Correlation and CausationConsider the Cenozoic era (the last 65 million years). Overall, solar activity increased 0.4% over this period. "Because Earth absorbs about 240 W/m^2 of solar energy, that brightness increase is a forcing of about 1 W/m^2. This small linear increase of forcing, by itself, would have caused a modest global warming through the Cenozoic Era. " The CO2 levels caused a much higher forcing. In contrast, atmospheric CO2 during the Cenozoic changed from at least 1000 ppm in the early Cenozoic to as small as 170 ppm during recent ice ages. The resulting climate forcing, as can be computed accurately for this CO2 range using formulae in Table 1 of Hansen et al. (2000), exceeds 10 W/m^2. It is clear that CO2 was the dominant climate forcing in the Cenozoic. "[1]In fact, the temperature changes correspond to the CO2 changes. ". .. there is a close correlation between Antarctic temperature and atmospheric concentrations of CO2 (Barnola et al. 1987). The extension of the Vostok CO2 record shows that the main trends of CO2 are similar for each glacial cycle. Major transitions from the lowest to the highest values are associated with glacial-interglacial transitions. During these transitions, the atmospheric concentrations of CO2 rises from 180 to 280-300 ppmv (Petit et al. 1999). The extension of the Vostok CO2 record shows the present-day levels of CO2 are unprecedented during the past 420 kyr. "[2]This graph shows the CO2-temperature correlation over the last 700,000 years: Excess CO2 traps heat. Considering the recent global warming, satellites measure less heat escaping out to space, at the particular wavelengths that CO2 absorbs heat, thus finding ". .. direct experimental evidence for a significant increase in the Earth's greenhouse effect. " In other words, the Earth is retaining more of the heat that it receives from the sun that it received from before. This excess heat manifests itself through global temperature increases. "If less heat is escaping to space, where is it going? Back to the Earth's surface. Surface measurements confirm this, observing more downward infrared radiation. A closer look at the downward radiation finds moreheat returning at CO2 wavelengths,leadin to the conclusion that '. .. this experimental data should effectively end the argument by skeptics that no experimental evidence exists for the connection between greenhouse gas increases in the atmosphere and global warming. '"[3][4][5]Evidence of Mankind's Influence on the Recent Global Warming TrendIt would be rather coincidental if the recent rise in global warming happened to start just around the time that humans started to emit large quantities of greenhouse gases. However, there is direct evidence as well, in addition to the already established correlation between temperature and CO2. Now, it is known that CO2 levels are increasing. "In pre-industrial times over the last 10,000 years, CO2 was relatively stable at around 275 to 285 parts per million. Over the last 250 years, atmospheric CO2 levels have increased by about 100 parts per million. " CO2 levels are increasing at a level not seen in at least 500,000 years, if not longer. [6]Here is a graph showing CO2 concentrations over the last 10000 years: [7][8]Now, carbon has several isotopes, three of which are C12, C13, and C14. C14 is radioactive, and has a half life of around 5,730 years. The CO2 emissions that humans make come from fossil fuels. Thus, if humans were the cause of the excess CO2, we'd except the C14/C12 ratio to decline, because, while there is a relatively constant amount of C14 in the atmosphere due to continuous replenishment (when a neutron collides with a regular nitrogen atom, a C14 atom and a proton result), the amount of C14 in the Earth has steadily decreased because it is not replenished, and since fossil fuels come from the ground, almost pure C12 is being ejected into the atmosphere. Indeed, it is observed that the C14/C12 ratio has declined. And thus, if humans were the cause of the excess CO2, we'd except the C13/C12 ratio to decline, because plants find it easier to take in carbon dioxide with a C12 atom than one with a C13 atom, implying that plants have a lower C13/C12 ratio than the atmopshere and, since animals eat plants (either by directly eating then or eating something that eats plants), also implying that fossils also have a lower C13/C12 ratio than the atmopshere, implying that we'd see a decline in the C13/C12 ratio as well. Indeed it is also observed that the C13/C12 ratio has declined. [9][10][11]This can be observed in the graph below (this is the C13/C12 ratio over the last 650 years; the C14/C12 ratio graph was too big to put in the debate): The evidence that this excess CO2 is the cause of the recent global warming is voluminous. One piece of evidence is a comparison of warming in the troposphere and stratosphere. Because the CO2 is in the upper troposphere, the troposphere temperature would increase, while the stratospheric temperature would decrease, because there would be less heat reaching the stratosphere. "Computer model estimates of the ‘human influence’ fingerprint are broadly similar to the observed pattern. In sharp contrast, model simulations of internal and total natural variability cannot produce the same sustained, large-scale warming of the troposphere and cooling of the stratosphere. "[4][12][13]This graph shows this: [4]Another piece of evidence is the frequency of cold days and nights. Because the sun only shines in the day time, is the sun was causing global warming, the days would warm faster than the nights, while if greenhouse gases were causing global warming, this wouldn't be observed. It is the latter's prediction that is observed. "What we observe is a decrease in cold nights greater than the decrease in cold days, and an increase in warm nights greater than the increase in warm days. "[4][14]This can be shown in the below graph: [4]Overall, the evidence shows that human-emitted greenhouse gases are the cause of global warming. CO2, in addition to other gases like methane and nitrous oxide are being emitted by humans in very large amounts, and this is manifesting itself in an increase in the average global temperature. Climate Sensitivity and FeedbacksClimate sensitivity is the amount the temperature would rise if the CO2 concentration were doubled. Obviously, if there's a large climate sensitivity, then increases in CO2 have large effect. It is known that the climate sensitivity is around 1 degree C. However, this can be amplified through feedbacks. Positive ones amplify the sensitivity, while negative ones diminish the sensitivity. The evidence overwhelmingly comes down on the former, that positive feedbacks are happening. Increases in CO2 cause temperature increases, which are amplified by water vapor and the effect on clouds. "Since the radiative effects associated with the buildup of water vapor to near-saturation levels and the subsequent condensation into clouds are far stronger than the equilibrium level of radiative forcing by the non-condensing GHGs, this results in large local fluctuations in temperature about the global equilibrium value. "[15]This can be shown in the below graph: Further, increases in CO2 affect the carbon cycle in this way: Global warming can result in the death of vegetation (due to droughts) and the warming of the ocean. Both of these further reduce the maximum absorption of the Earths carbon cycle, thus resulting in even more CO2 being released into the atmosphere. And with this, CO2 increases even more. In other words, CO2-caused temperature increases are amplified by positive feedbacks and the mechanics of the carbon cycle. So, the positive feedback amplifies the climate sensitivity. How much it is amplified can be determined through study. Using a Bayesian statistical approach, which is “the dominant [method] in the literature”, these findings support the notion of climate sensitivity as maximum 4 degrees C, a mean of 3 degrees C, and likely not lower than 3 degrees. [16]The graph below gives a statistical analysis: [17]The mean is around 3 degrees C. The CO2 that humans emit thus has an effect of 3 degrees C per doubling of CO2. This can be shown by the fact that CO2 concentrations have increased from around 275 ppm to around 400 ppm. This is an increase of around 40%. This should manifest itself with a temperature increase of a little less than 1.5 degrees C. Indeed, temperatures have increased around this amount over the last 150 years. The anthropogenic-forcing climate models thus match observations. [18]In other words, in addition to the direct evidence of how the Earth is warming, the climate models based on a greenhouse gas cause to global warming explain almost perfectly the recent global warming. This is a lot of evidence for a human case to the recent global warming. ConclusionGreenhouse gases cause global warming because of their heat trapping abilities. Humans have been emitting vast amounts of greenhouse gases over the last 150 years, and this shows itself on the CO2 measurements. The atmospheric warming pattern and greater heating at night are evidence that the recent global warming is caused by those human emitted greenhouse gases. These increases are amplified through the water vapor and cloud positive feedbacks and the positive feedback that arises through the climate cycle. The climate sensitivity ends up being around 3 degrees C. Finally, the CO2-temperature record shows that the two correlate with remarkable correlation. SourcesSources in comments.

Humanity is the main cause of global warming. Firstly. I have not quantified anything in the heading of the debate. I've said 'main cause'. Not 'more than fifty percent' or somethinglike that. Main means a major portion. Since when did 'substantially' get used for a small portion? And it is also not my possible (to my knowledge) to quantify the impact of natural causes on climate change as it is unpredictable and can change any time. Con has also left out my point that human activities can alter the natural conditions of the earth, therefore any change in temperature due to natural causes could have a human factor behind it. As explained in the following. http://co2now.org... Secondly, I never said natural causes play an insignificant role. I said they play an important role but not as important as human causes. In con's reference chart, the temperature has been constantly oscillating between hot and cold, but if you check recent years there have been almost two constant hot periods and the cold period is almost invisible ( in the graph I mean) meaning it is very short. And then in the graph itself it clear that the hot periods have been on the rise since the Age of Induatrialization. And after 2015, the cold period is based on assumptions and predictions, and as I have already made clear that nature cannot always be predicted. Thirdly Global Warming is a reality. Just because there have hotter periods before, doesn't mean it is not happening. The following site also explains that the global warming hiatus in recent times is not true. And that climate only causes short term changes in the climate of the earth, but human activity causes long term changes. http://www.bbc.com... Fourthly scientists will not quanitfy and agree that mankind is responsible for global warming, as it is their community that are primary responsible (in humans). But I will not defame them as some ARE trying their best to prove it. Fifthly , again I refer to the chart provided by Con, the hot periods have gradually developed over a period of time, but in recent years its almost at a right angle. Which means there have been sharp and quick increase in the heat all over the globe.

September Beginners Tournament: Man and Global Warming I affirm and thank 101 for this debate. == My case ==C1) Existence of a scientific consensus on climate changeThe scientific opinion on climate change is clear that mankind is probably the main cause of global warming. In fact, a survey has concluded that there are no scientifically relevant studies that provide a direct rebuttal to the idea that mankind is the main cause of global warming. [1] The IPCC, the American Meteorological Society, American Geophysical Union, and the American Association for the Advancement of Science all agree that the evidence for human-caused global warming dominating climate change is overwhelming and clear. [1] "That humans are causing global warming is the position of the Academies of Science from 80 countries plus many scientific organizations that study climate science. More specifically, around 95% of active climate researchers actively publishing climate papers endorse the consensus position." [2] A study by Doran (2009) found that 82% of climate scientists with a master degree or Ph.D agreed that mankind is the main cause of global warming. [3] NASA agrees, and notes that "most of the leading scientific organizations worldwide have issued public statements endorsing this position . . . Ninety-seven percent of climate scientists agree that climate-warming trends over the past century are very likely due to human activities." [4] A report written by 28 scientists representing 13 governmental agencies has stated, "The global warming of the past 50 years is primarily due to human-induced increases in heat-trapping gases." [5] C2) Human-induced increases in carbon dioxideAll scientists agree that carbon dioxide traps heat. That carbon dioxide traps heat is basic physics. Excess carbon dioxide traps heat. Harries, et al. (2001) finds "direct experimental evidence for a significant increase in the Earth's greenhouse effect" at the wavelength bands where carbon dioxide and methane trap heat. [6] The debate on carbon dioxide comes down to "climate sensitivity," defined as the increase in global land-sea mean temperature per doubling of carbon dioxide concentration in the Earth's atmosphere. All serious skeptical scientists and supporters of global warming agree that -- in a default state -- the climate sensitivity is likely 1.1 degrees Celsius. [7] The argument is about feedbacks. What are feedbacks? Feedbacks are mechanisms -- such as clouds and volcanic activity -- that amplify or dampen the effect that carbon dioxide has on temperature. The mechanisms that amplify the effect are called positive feedbacks, while those that dampen it are called negative feedbacks. [8] I argue that positive feedbacks dominate climate. Many studies agree. "Since the radiative effects associated with the buildup of water vapor to near-saturation levels and the subsequent condensation into clouds are far stronger than the equilibrium level of radiative forcing by the non-condensing GHGs, this results in large local fluctuations in temperature about the global equilibrium value." [9] This is demonstrated in the below graph: In simpler explanation, a feedback amplifies the effect of a forcing -- in this case, carbon dioxide. Using a Bayesian statistical approach, which is the "dominant" method in the literature, one can conclude that the average climate sensitivity is four degrees Celsius. [9] It is empirically demonstrable that climate sensitivity is at least three degrees Celsius. CO2 concentrations have increased from around 275 ppm to 400 ppm -- a 40% increase. This should manifest itself with a temperature increase of a little less than 1.5 degrees C. And temperature levels have increased precisely to this amount. [10] Below is a graph that showcases how much sensitivity different studies have found. [13] The following picture demonstrates the evidence that shows a climate sensitivity of around 3 degrees Celsius. It is well-known that CO2 levels are increasing. The below graph shows a direct rise in CO2 levels. [11] Much of CO2 increase is human-induced. "In pre-industrial times over the last 10,000 years, CO2 was relatively stable at around 275 to 285 parts per million. Over the last 250 years, atmospheric CO2 levels have increased by about 100 parts per million." [12] C3) Paleoclimatology suggests that mankind causes global warmingMultiple paleoclimate records suggest that CO2 has a direct effect on climate change. According to many studies, after the beginning of the Cenozoic Era 65.5 million years ago, carbon dioxide has been the dominant climate forcing. [14] The sun increased slightly over that time period, whereas temperatures cooled. CO2, however, fell steadily through that time period. An ideal example of this is the Vostok ice cores. "There is a close correlation between Antarctic temperature and atmospheric concentrations of CO2 (Barnola et al. 1987). The extension of the Vostok CO2 record shows that the main trends of CO2 are similar for each glacial cycle. Major transitions from the lowest to the highest values are associated with glacial-interglacial transitions. During these transitions, the atmospheric concentrations of CO2 rises from 180 to 280-300 ppmv (Petit et al. 1999). The extension of the Vostok CO2 record shows the present-day levels of CO2 are unprecedented during the past 420 kyr." [15] The below graph documents the correlation between increase in CO2 concentration and rise in temperature over 700,000 years. In fact, 2014 was the warmest year since 1400, suggesting that increased human activity drives climate change. Therefore, I conclude that human emissions increase temperatures, and, thus, mankind is the main cause of global warming. == Sources ==[1]: http://www.sciencemag.org...[2]: http://www.skepticalscience.com...[3]: http://tigger.uic.edu...[4]: http://climate.nasa.gov...[5]: http://downloads.globalchange.gov...[6]: http://skepticalscience.net...[7]: https://mises.org...[8]: Roy Spencer, "The Great Global Warming Blunder," p. 54[9]: http://www.giss.nasa.gov...[10]: https://www2.ucar.edu...[11]: http://www.esrl.noaa.gov...[12]: http://www.skepticalscience.com...[13]: http://www.skepticalscience.com...[14]: http://www.columbia.edu...[15]: http://cdiac.ornl.gov...

Mankind Is the Main Cause of Global Warming CO2's Effect on TemperatureFirst, correlation. The climate data over the last 700,000 years or so show that temperature and CO2 track very close to each other. ". .. there is a close correlation between Antarctic temperature and atmospheric concentrations of CO2. The extension of the Vostok CO2 record shows that the main trends of CO2 are similar for each glacial cycle. Major transitions from the lowest to the highest values are associated with glacial-interglacial transitions. During these transitions, the atmospheric concentrations of CO2 rises from 180 to 280-300 ppmv. The extension of the Vostok CO2 record shows the present-day levels of CO2 are unprecedented during the past 420 kyr. "[1]This graph shows the CO2-temperature correlation over the last 650,000 years[2]: CO2 can be the dominant forcing for the climate. Consider the Cenozoic era (the last 65 million years). Overall, solar activity increased 0.4% over this period. "Because Earth absorbs about 240 W/m^2 of solar energy, that brightness increase is a forcing of about 1 W/m^2. This small linear increase of forcing, by itself, would have caused a modest global warming through the Cenozoic Era. " The CO2 levels caused a much higher forcing. "In contrast, atmospheric CO2 during the Cenozoic changed from at least 1000 ppm in the early Cenozoic to as small as 170 ppm during recent ice ages. The resulting climate forcing, as can be computed accurately for this CO2 range. .. exceeds 10 W/m^2. It is clear that CO2 was the dominant climate forcing in the Cenozoic. "[3]But then, there's also the matter of causation. CO2's effect on temperature can be explained by appealing to the carbon cycle. The Earth receives all of its energy from the sun. Some of this is reflected by the Earth's surface and by clouds and other particles present in the atmosphere. In addition, some of the built up energy in the Earth's surface can be emitted back into the atmosphere. Greenhouse gases like CO2, methane, and nitrous oxide trap some of this emitted heat by reflecting the radiation back to the surface. However, greater concentrations of greenhouse gases cause more of the energy that is being emitted from the surface to be reflected back to the surface. This causes more heat to build up, warming the planet. [4]Now consider climate sensitivity. Climate sensitivity is the amount the temperature would rise if the CO2 concentration were doubled. Obviously, if there's a large climate sensitivity, then increases in CO2 have large effect. It is known that the climate sensitivity is around 1 degree C. However, this can be amplified through feedbacks. Positive ones amplify the sensitivity, while negative ones diminish the sensitivity. The evidence overwhelmingly comes down on the former, that positive feedbacks are happening. Increases in CO2 cause temperature increases, which are amplified by water vapor and the effect on clouds. "Since the radiative effects associated with the buildup of water vapor to near-saturation levels and the subsequent condensation into clouds are far stronger than the equilibrium level of radiative forcing by the non-condensing GHGs, this results in large local fluctuations in temperature about the global equilibrium value. "[5]This can be shown in the below graph[5]: Now back to the carbon cycle. Global warming can result in the death of vegetation (due to droughts) and the warming of the ocean. Both of these further reduce the maximum absorption of the Earths carbon cycle, thus resulting in even more CO2 being released into the atmosphere. And with this, CO2 increases even more. In other words, CO2-caused temperature increases are amplified by positive feedbacks and the mechanics of the carbon cycle. So, the positive feedback amplifies the climate sensitivity. How much it is amplified can be determined through study. Using a Bayesian statistical approach, which is “the dominant [method] in the literature”, these findings support the notion of climate sensitivity as maximum 4 degrees C, a mean of 3 degrees C, and likely not lower than 3 degrees. [6]The graph below gives a statistical analysis[7]: The mean is around 3 degrees C. The CO2 that humans emit thus has an effect of 3 degrees C per doubling of CO2. This can be shown by the fact that CO2 concentrations have increased from around 275 ppm to around 400 ppm. This is an increase of around 40%. This should manifest itself with a temperature increase of a little less than 1.5 degrees C. Indeed, temperatures have increased around this amount over the last 150 years. The anthropogenic-forcing climate models thus match observations. [8]In other words, in addition to the direct evidence of how the Earth is warming, the climate models based on a greenhouse gas cause to global warming explain almost perfectly the recent global warming. This is a lot of evidence for a human case to the recent global warming. Humans' Emission of CO2It would be rather coincidental if the recent rise in global warming happened to start just around the time that humans started to emit large quantities of greenhouse gases. However, there is direct evidence as well, in addition to the already established correlation between temperature and CO2. Now, it is known that CO2 levels are increasing. "In pre-industrial times over the last 10,000 years, CO2 was relatively stable at around 275 to 285 parts per million. Over the last 250 years, atmospheric CO2 levels have increased by about 100 parts per million. " CO2 levels are increasing at a level not seen in at least 500,000 years, if not longer. [9]Here is a graph showing CO2 concentrations over the last 10000 years[10][11]: The evidence that this excess CO2 is the cause of the recent global warming is voluminous. One of the biggest indicators is the fact that less heat is escaping into space. Satellites measure less heat escaping out into space, particularly at the specific wavelengths that CO2 absorbs. In other words, the Earth is retaining a greater percentage of the heat that it receives from the sun than it did before. This excess heat manifests itself through global temperature increases. "If less heat is escaping to space, where is it going? Back to the Earth's surface. Surface measurements confirm this, observing more downward infrared radiation. A closer look at the downward radiation finds more heat returning at CO2 wavelengths, leading to the conclusion that '. .. this experimental data should effectively end the argument by skeptics that no experimental evidence exists for the connection between greenhouse gas increases in the atmosphere and global warming. '"[12][13][14]Another piece of evidence is a comparison of warming in the troposphere and stratosphere. Because the CO2 is in the upper troposphere, the troposphere temperature would increase, while the stratospheric temperature would decrease, because there would be less heat reaching the stratosphere. "Computer model estimates of the ‘human influence’ fingerprint are broadly similar to the observed pattern. In sharp contrast, model simulations of internal and total natural variability cannot produce the same sustained, large-scale warming of the troposphere and cooling of the stratosphere. "[12][15][16]This graph shows this[15]: Related to this is the fact that the tropopause, the boundary between the troposphere and stratosphere, is rising. This is because the temperature gradient between the top of the troposphere and the bottom of the stratosphere is greater, as just described above. This causes the warmer air from the troposphere to rise, pushing the troposphere up. "Observations indicate that the height of the tropopause - the boundary between the stratosphere and troposphere - has increased by several hundred meters since 1979. "[12][17]Another related piece of evidence to this is the cooling of the ionosphere. The ionosphere is the layer of the Earth's atmosphere where ionization takes place. It comprises the upper mesosphere, thermosphere, and lower exosphere. More precisely, it extends from 60 km to 1000 km above the surface. Studies indicate, ". .. moderate negative trends of about 2 to 3 K per decade at heights of 50 to 70 km. .. slightly larger cooling trends at heights of 70 to 80 km in the low and middle latitudes. .. essentially zero temperature trends between 80 and 100 km. .. at heights near 350 km, a negative trend of about –17 K per decade. "[12][18]Yet another piece of evidence is the frequency of cold days and nights. Because the sun only shines in the day time, if the sun was causing global warming, the days would warm faster than the nights, while if greenhouse gases were causing global warming, this wouldn't be observed. It is the latter's prediction that is observed. "What we observe is a decrease in cold nights greater than the decrease in cold days, and an increase in warm nights greater than the increase in warm days. "[12][15][19]This can be shown in the below graph[15]: Overall, the evidence shows that human-emitted greenhouse gases are the main cause of global warming. CO2, in addition to other greenhouse gases like methane and nitrous oxide are being emitted by humans in very large amounts, and this is manifesting itself in an increase in the average global temperature. ConclusionGreenhouse gases cause global warming because of their heat trapping abilities. Humans have been emitting vast amounts of greenhouse gases over the last 150 years, and this shows itself on the CO2 measurements. The atmospheric warming pattern and greater heating at night are evidence that the recent global warming is caused by those human emitted greenhouse gases. These increases are amplified through the water vapor and cloud positive feedbacks and the positive feedback that arises through the climate cycle. The climate sensitivity ends up being around 3 degrees C. Finally, the CO2-temperature record shows that the two correlate with remarkable correlation. SourcesSources in comments.

Mankind Is the Main Cause of Global Warming CO2's Effect on TemperatureFirst, correlation. The climate data over the last 700,000 years or so show that temperature and CO2 track very close to each other. ". .. there is a close correlation between Antarctic temperature and atmospheric concentrations of CO2. The extension of the Vostok CO2 record shows that the main trends of CO2 are similar for each glacial cycle. Major transitions from the lowest to the highest values are associated with glacial-interglacial transitions. During these transitions, the atmospheric concentrations of CO2 rises from 180 to 280-300 ppmv. The extension of the Vostok CO2 record shows the present-day levels of CO2 are unprecedented during the past 420 kyr. "[1]This graph shows the CO2-temperature correlation over the last 650,000 years[2]: CO2 can be the dominant forcing for the climate. Consider the Cenozoic era (the last 65 million years). Overall, solar activity increased 0.4% over this period. "Because Earth absorbs about 240 W/m^2 of solar energy, that brightness increase is a forcing of about 1 W/m^2. This small linear increase of forcing, by itself, would have caused a modest global warming through the Cenozoic Era. " The CO2 levels caused a much higher forcing. "In contrast, atmospheric CO2 during the Cenozoic changed from at least 1000 ppm in the early Cenozoic to as small as 170 ppm during recent ice ages. The resulting climate forcing, as can be computed accurately for this CO2 range. .. exceeds 10 W/m^2. It is clear that CO2 was the dominant climate forcing in the Cenozoic. "[3]But then, there's also the matter of causation. CO2's effect on temperature can be explained by appealing to the carbon cycle. The Earth receives all of its energy from the sun. Some of this is reflected by the Earth's surface and by clouds and other particles present in the atmosphere. In addition, some of the built up energy in the Earth's surface can be emitted back into the atmosphere. Greenhouse gases like CO2, methane, and nitrous oxide trap some of this emitted heat by reflecting the radiation back to the surface. However, greater concentrations of greenhouse gases cause more of the energy that is being emitted from the surface to be reflected back to the surface. This causes more heat to build up, warming the planet. [4]Now consider climate sensitivity. Climate sensitivity is the amount the temperature would rise if the CO2 concentration were doubled. Obviously, if there's a large climate sensitivity, then increases in CO2 have large effect. It is known that the climate sensitivity is around 1 degree C. However, this can be amplified through feedbacks. Positive ones amplify the sensitivity, while negative ones diminish the sensitivity. The evidence overwhelmingly comes down on the former, that positive feedbacks are happening. Increases in CO2 cause temperature increases, which are amplified by water vapor and the effect on clouds. "Since the radiative effects associated with the buildup of water vapor to near-saturation levels and the subsequent condensation into clouds are far stronger than the equilibrium level of radiative forcing by the non-condensing GHGs, this results in large local fluctuations in temperature about the global equilibrium value. "[5]This can be shown in the below graph[5]: Now back to the carbon cycle. Global warming can result in the death of vegetation (due to droughts) and the warming of the ocean. Both of these further reduce the maximum absorption of the Earths carbon cycle, thus resulting in even more CO2 being released into the atmosphere. And with this, CO2 increases even more. In other words, CO2-caused temperature increases are amplified by positive feedbacks and the mechanics of the carbon cycle. So, the positive feedback amplifies the climate sensitivity. How much it is amplified can be determined through study. Using a Bayesian statistical approach, which is “the dominant [method] in the literature”, these findings support the notion of climate sensitivity as maximum 4 degrees C, a mean of 3 degrees C, and likely not lower than 3 degrees. [6]The graph below gives a statistical analysis[7]: The mean is around 3 degrees C. The CO2 that humans emit thus has an effect of 3 degrees C per doubling of CO2. This can be shown by the fact that CO2 concentrations have increased from around 275 ppm to around 400 ppm. This is an increase of around 40%. This should manifest itself with a temperature increase of a little less than 1.5 degrees C. Indeed, temperatures have increased around this amount over the last 150 years. The anthropogenic-forcing climate models thus match observations. [8]In other words, in addition to the direct evidence of how the Earth is warming, the climate models based on a greenhouse gas cause to global warming explain almost perfectly the recent global warming. This is a lot of evidence for a human case to the recent global warming. Humans' Emission of CO2It would be rather coincidental if the recent rise in global warming happened to start just around the time that humans started to emit large quantities of greenhouse gases. However, there is direct evidence as well, in addition to the already established correlation between temperature and CO2. Now, it is known that CO2 levels are increasing. "In pre-industrial times over the last 10,000 years, CO2 was relatively stable at around 275 to 285 parts per million. Over the last 250 years, atmospheric CO2 levels have increased by about 100 parts per million. " CO2 levels are increasing at a level not seen in at least 500,000 years, if not longer. [9]Here is a graph showing CO2 concentrations over the last 10000 years[10][11]: The evidence that this excess CO2 is the cause of the recent global warming is voluminous. One of the biggest indicators is the fact that less heat is escaping into space. Satellites measure less heat escaping out into space, particularly at the specific wavelengths that CO2 absorbs. In other words, the Earth is retaining a greater percentage of the heat that it receives from the sun than it did before. This excess heat manifests itself through global temperature increases. "If less heat is escaping to space, where is it going? Back to the Earth's surface. Surface measurements confirm this, observing more downward infrared radiation. A closer look at the downward radiation finds more heat returning at CO2 wavelengths, leading to the conclusion that '. .. this experimental data should effectively end the argument by skeptics that no experimental evidence exists for the connection between greenhouse gas increases in the atmosphere and global warming. '"[12][13][14]Another piece of evidence is a comparison of warming in the troposphere and stratosphere. Because the CO2 is in the upper troposphere, the troposphere temperature would increase, while the stratospheric temperature would decrease, because there would be less heat reaching the stratosphere. "Computer model estimates of the ‘human influence’ fingerprint are broadly similar to the observed pattern. In sharp contrast, model simulations of internal and total natural variability cannot produce the same sustained, large-scale warming of the troposphere and cooling of the stratosphere. "[12][15][16]This graph shows this[15]: Related to this is the fact that the tropopause, the boundary between the troposphere and stratosphere, is rising. This is because the temperature gradient between the top of the troposphere and the bottom of the stratosphere is greater, as just described above. This causes the warmer air from the troposphere to rise, pushing the troposphere up. "Observations indicate that the height of the tropopause - the boundary between the stratosphere and troposphere - has increased by several hundred meters since 1979. "[12][17]Another related piece of evidence to this is the cooling of the ionosphere. The ionosphere is the layer of the Earth's atmosphere where ionization takes place. It comprises the upper mesosphere, thermosphere, and lower exosphere. More precisely, it extends from 60 km to 1000 km above the surface. Studies indicate, ". .. moderate negative trends of about 2 to 3 K per decade at heights of 50 to 70 km. .. slightly larger cooling trends at heights of 70 to 80 km in the low and middle latitudes. .. essentially zero temperature trends between 80 and 100 km. .. at heights near 350 km, a negative trend of about –17 K per decade. "[12][18]Yet another piece of evidence is the frequency of cold days and nights. Because the sun only shines in the day time, if the sun was causing global warming, the days would warm faster than the nights, while if greenhouse gases were causing global warming, this wouldn't be observed. It is the latter's prediction that is observed. "What we observe is a decrease in cold nights greater than the decrease in cold days, and an increase in warm nights greater than the increase in warm days. "[12][15][19]This can be shown in the below graph[15]: Overall, the evidence shows that human-emitted greenhouse gases are the main cause of global warming. CO2, in addition to other greenhouse gases like methane and nitrous oxide are being emitted by humans in very large amounts, and this is manifesting itself in an increase in the average global temperature. ConclusionGreenhouse gases cause global warming because of their heat trapping abilities. Humans have been emitting vast amounts of greenhouse gases over the last 150 years, and this shows itself on the CO2 measurements. The atmospheric warming pattern and greater heating at night are evidence that the recent global warming is caused by those human emitted greenhouse gases. These increases are amplified through the water vapor and cloud positive feedbacks and the positive feedback that arises through the climate cycle. The climate sensitivity ends up being around 3 degrees C. Finally, the CO2-temperature record shows that the two correlate with remarkable correlation. SourcesSources in comments.

Mankind Is the Main Cause of Global Warming Overviews OV1: I *did* define ‘global warming’ in R1, thus Con’s objection regarding there being no definition of global warming is invalid. OV2: The first round was supposed to be *only* for acceptance--thus, I request Con to pass the final round to equalize the # of rounds. OV3: I shall only present my own case in this round, and rebut Con’s case in the next. C1) Climate sensitivity is likely high CO2 climate sensitivity is the rise in equilibrium temperature with rise in CO2 concentration in the Earth’s atmosphere [1], especially calculated with a 2x rise in CO2 levels and its correlation with atmospheric temperature levels. Idso (1998) and Shaviv (2005) predict that non-amplified mean CO2 sensitivity is 1 degree celsius [2][3], thus there would be a 1 degree celsius rise in temperature with doubling CO2 concentration. But the effects of CO2 on equilibrium atmospheric temperature is amplified by climate feedbacks. A feedback is something that causes a variation in sensitivity via. generally environmental means [4], and can be positive or negative in nature. A positive feedback is a feedback that causes a rise in overall climate sensitivity, while a negative feedback causes a drop in climate sensitivity [5]. Various studies report positive feedbacks as more likely. Soden and Held (2005) reported a 2 degree celsius climate sensitivity due to positive feedbacks [6]. The study reports very few negative feedbacks. “Water vapor is found to provide the largest positive feedback in all models and its strength is consistent with that expected from constant relative humidity changes in the water vapor mixing ratio. The feedbacks from clouds and surface albedo are also found to be positive in all models, while the only stabilizing (negative) feedback comes from the temperature response.” [7] Colman (2003) reports a feedback of nearly 3 degrees celsius, and the paper is cited by Soden and Held. In the study, “[a] comparison is performed for water vapour, cloud, albedo and lapse rate feedbacks taken from published results of ‘offline’ feedback calculations for general circulation models (GCMs) with mixed layer oceans performing 2 x CO2 and solar perturbation experiments.” [8] There is much evidence outside climate models as well. Wigley, et al. (2005) reports a possible sensitivity of greater than 4.5 degrees celsius due to extremely high positive feedback levels, and supports an average sensitivity of 3.5 degrees [9]. The study says, “After the maximum cooling for low-latitude eruptions the temperature relaxes back toward the initial state with an e-folding time of 29–43 months for sensitivities of 1–4 degrees C equilibrium warming for CO2 doubling.” [10] Additionally, using volcanic activity, Forster and Gregory (2005) predict an amplified climate sensitivity of around 1 to 4.1 degrees C [11]. Even in a hypothetical scenario where negative feedbacks cancel out positive feedbacks to a climate sensitivity of 1 degree C, research by Ziskin and Shaviv (2011) has predicted that “the largest contribution to the 20th century warming comes from anthropogenic sources.” [12] They find that of the ~0.7 degree C temperature rise in the 20th century (some estimates slightly higher), about 0.4 degrees of that are due to anthropogenic forgings, or about 57% of the warming. A significant body of research notes that climate sensitivity is probably much higher, approximately 3 degrees C with a range of 2 to 4.5 degrees C. Their findings can be seen in the graph below [13]. Thus, I have demonstrated that climate sensitivity is high and the climate system is predominated by positive feedback mechanisms. C2) Paleoclimate In the Cenozoic era (the last 65 million years), overall solar activity has risen 0.4%. “Because Earth absorbs about 240 W/m^2 of solar energy, that brightness increase is a forcing of about 1 W/m^2. This small linear increase of forcing, by itself, would have caused a modest global warming through the Cenozoic Era.” [14] The study reports that carbon dioxide is the dominant force behind temperature rise and rise in solar activity in the Cenozoic. Royer, et al. (2004) notes that CO2 drives Phanerozoic temperature, and writes, “Atmospheric CO2 is an important greenhouse gas, and because of its short residence time (~4 yr) and numerous sources and sinks, it has the potential to regulate climate over a vast range of timescales, from years to millions of years.” [15] The temperature changes of the Cenozoic correspond to CO2 changes. “[T]here is a close correlation between Antarctic temperature and atmospheric concentrations of CO2 (Barnola et al. 1987). The extension of the Vostok CO2 record shows that the main trends of CO2 are similar for each glacial cycle. Major transitions from the lowest to the highest values are associated with glacial-interglacial transitions. During these transitions, the atmospheric concentrations of CO2 rises from 180 to 280-300 ppmv (Petit et al. 1999). The extension of the Vostok CO2 record shows the present-day levels of CO2 are unprecedented during the past 420 kyr.” [16] Harries, et al. (2001) finds that CO2 traps solar radiation, thus increasing solar radiation’s interaction with the Earth’s atmospheric temperatures [17]. Satellites have reportedly found “direct experimental evidence for a significant increase in the Earth's greenhouse effect [because of CO2].” [18] It is known that CO2 levels are increasing. “In pre-industrial times over the last 10,000 years, CO2 was relatively stable at around 275 to 285 parts per million. Over the last 250 years, atmospheric CO2 levels have increased by about 100 parts per million.” [19] The graph below illustrates increasing CO2 levels [20]. It is well known that carbon dioxide is the primary greenhouse gas emitted through human activity. “Human activities are altering the carbon cycle—both by adding more CO2 to the atmosphere and by influencing the ability of natural sinks, like forests, to remove CO2 from the atmosphere. While CO2 emissions come from a variety of natural sources, human-related emissions are responsible for the increase that has occurred in the atmosphere since the industrial revolution.” [21] It is, according to most paleoclimatological studies, warmer now than the Roman warm period or the medieval warm period, primarily because of human-caused CO2 influence [22]. Thus, I affirm. Over to Con. 1. http://www.pik-potsdam.de... 2. http://www.int-res.com... 3. http://onlinelibrary.wiley.com... 4. http://www.scribd.com... 5. http://www.ipcc.ch... 6. http://www.gfdl.noaa.gov... 7. Ibid. 8. http://link.springer.com... 9. http://onlinelibrary.wiley.com... 10. Ibid. 11. http://homepages.see.leeds.ac.uk... 12. http://www.phys.huji.ac.il... 13. http://www.iac.ethz.ch... 14. http://www.columbia.edu... 15. http://droyer.web.wesleyan.edu... 16. http://cdiac.ornl.gov... 17. http://www.nature.com... 18. Ibid. 19. http://www.skepticalscience.com... 20. http://www.esrl.noaa.gov... 21. http://www.epa.gov... 22. http://www.atmosp.physics.utoronto.ca...

Mankind Is the Main Cause of Global Warming Pass.

Mankind Is Not the Main Cause of Global Warming Thanks to subutai for posting an excellent opening round! I'm looking forward to this debate, as I am sure it will be an interesting one!So to kick this thing off I'd like to start by providing the readers with a quick road map of my case and how I aim to negate the given resolution.What I am going to do is set up the basis of a cause effect relationship between greenhouse gases (Such as CO2, Methane, and Water Vapor) and a warming trend, and then confirm this relationship with corroborating corollaries. This will prove that increased atmospheric GHG concentrations to create a warming effect on the climate.Next, I will begin to discuss why humanities effect on the climate creates an increased concentration of atmospheric greenhouse gases, thus creating an anthropogenic cause for global warming.Then, I will establish why the current warming trend cannot be due primarily to natural causes.Finally, to seal in these arguments, I will discuss the consensus of the scientific community as a whole regarding anthropogenic global warming.Con's CaseI. The Greenhouse effect and Greenhouse GasesTo begin, let's examine what exactly makes a green house gas, a green house gas. Everyone has likely heard of the most common GHGs: Carbon Dioxide (CO2), Methane (CH4), and Water Vapor (H2O). Why, though, do these gases cause a warming effect, while the gases most prevalent in our atmosphere, Nitrogen and Oxygen, cause no warming? A) Di-pole momentExamine the following diagram describing the molecular structures of the gases above. So here we have CO2, Methane, Water Vapor, Nitrogen, and Oxygen in either 3d models, or Lewis structures. The thing we must pay closest attention to is their molecular shape (VSEPR Theory). Carbon Dioxide is bent. Methane is tetrahedral. H2O is Bent. Nitrogen and oxygen, however, are Linear diatomic molecules [1].Now, every element has a different level of electronegativity. In an atom with an electronegativity disparity, a dipole moment forms [2]. This is essentially the formation of a magnetic field direction. CO2 and H2O due to their bent asymmetrical shapes have Dipole moments. The dipole moment "points" from the more electronegative towards the less electronegative. More +--> LessWhen an atom is struck by particular wavelengths of infrared light, the bonds in the atom begin to "vibrate" there are many kinds of vibration that can occur (bending, stretching, etc). [3] This causes the molecules to shift around, and in greenhouse gases, the dipole moment is shifted. Now atoms like N2 and O2 have no dipole moment, and no amount of shifting disrupts their symmetry. CO2 and H2O always have their dipole moment shifted by molecular vibration. Methane, due to the complexity of tetrahedral molecular shape, can undergo several vibrations that disrupt the symmetry of the molecule, and cause dipole moments to form.When a dipole moment is shifted or formed, much energy is released as heat. This is what happens in greenhouse gases [4].This is why greenhouse gases heat the earth when they are present in the atmosphere. Light from the sun strikes the molecule, and the infrared spectra that result in molecular vibration release heat energy into the atmosphere. Every single one of the billions of GHGs in the atmosphere are each acting as individual heat generators, catching and trapping energy from the sun, and heating the earth.B) Corollaries (Paleoclimate)Paleoclimates have historically been a major focal point of many debates on anthropogenic global warming. Therefore, I will preempt these arguments, so that time may be saved in the rebuttals. I will also reestablish the cause that I have described previously, and corroborate through corollaries.Many climate change skeptics have claimed that there is "No historic correlation" between the presence of green-house gases and global temperature. According to Royers 2006 [4] the data previously observed on the phanerzoic era has been contaminated, as it has not been adjusted for pH, which affects the molecular shape, atmospheric concentration, dipole moment, and molecular vibration potential of CO2. Quote Royer, "the temperature data correlate strongly with both the record of continental gla-ciation and atmospheric CO2". Furthermore, the famous Vostok Ice Cores show that "there is a close correlation between Antarctic temperature and atmospheric concentrations of CO2 (Barnola et al. 1987). The extension of the Vostok CO2 record shows that the main trends of CO2 are similar for each glacial cycle. Major transitions from the lowest to the highest values are associated with glacial-interglacial transitions. During these transitions, the atmospheric concentrations of CO2 rises from 180 to 280-300 ppmv (Petit et al. 1999). The extension of the Vostok CO2 record shows the present-day levels of CO2 are unprecedented during the past 420 kyr." [5]During the cenzoic period as well, CO2 was the driving force of Global warming, cite Hansen and Sato [6].II. Climate Sensitivity/CarbonAnother aspect of global warming that one must consider is "Climate sensitivity." Climate sensitivity is essentially the amount of expected change in global temperature as a result of increased retention of radiation (via GHGs). [7] Essentially, climate sensitivity tells us how much the temperature will change, given a certain amount of CO2 concentration increase [8] [10]. The reason that certain paleoclimates were not nearly as warm given the increased concentration of CO2 was due to lower climate sensitivity [9].Current studies have established an accepted measurement of modern climate sensitivity (a range between 1-4.1 degrees Celsius per doubling of CO2). This number is accepted by both supporters and skeptics of global warming [11].Furthermore, to preempt a rebuttal on the presence of water vapor concentrations, it has been observed that global humidity is increasing [12] [13].A) Carbon Cycle, atmospheric CO2, and "Tipping the Pot"A common rebuttal against the anthropogenic climate change case is the relative smallness of man-made CO2 compared to natural concentrations. The problem with this argument, is that it observes all carbon, rather than only atmospheric CO2. Carbon that is not in the atmosphere cannot affect climate change, and does not contribute to global warming. It can be seen that man-made CO2 almost always remains in the atmosphere, as the natural equilibrium of the earths carbon cycle is upset by the introduction of artificial CO2 And now in the industrial age where CO2 is introduced into the atmosphere in a myriad of ways, we can see that atmospheric CO2 levels are at a record level. Then, as GHGs warm the Earth, positive feedback loops occur. Thus, humanity has "tipped the pot."B) Positive FeedbackPositive feedback comes in many forms in climate change. The problem with global warming, is that said warming can result in the death of vegetation (due to droughts) and the warming of the ocean. Both of these further reduce the maximum absorption of the Earths carbon cycle, thus resulting in even more CO2 being released into the atmosphere. [14]These kinds of emissions are referred to as "indirect emissions" as humans did not directly produce these GHG emissions, they are directly responsible for the factors that resulted in this emission. This emission also comes from other human practices, such as deforestation, and pollution of the ocean.III. What makes anthropogenic warming different from natural warming?The key difference between the current modern global warming, and previous eras of natural warming, is that the current warming period is undoubtedly the fastest in the Earth's history. "Carbon dioxide and other global warming pollutants are collecting in the atmosphere like a thickening blanket, trapping the sun's heat and causing the planet to warm up. Although local temperatures fluctuate naturally, over the past 50 years the average global temperature has increased at the fastest rate in recorded history." The Global scientific community has reached a 97% consensus that the current trend cannot be accounted for by natural forces. 18 scientific associations have examined and produced data on the climate, and have stated "Observations throughout the world make it clear that climate change is occurring, and rigorous scientific research demonstrates that the greenhouse gases emitted by human activities are the primary driver."[15][16][17][18][19][20][21]This is not an appeal to authority, as every single one of these quotes a backed by countless empirically verified, and peer reviewed studies. This is not a claim made by a single scientist, this is an overwhelming preponderance of evidence.A) Atmospheric Carbon Levels Atmospheric carbon levels, as previously mentioned, have never been this high. Record breaking levels of CO2 (a known GHG) have acted upon the Earth. Never before have atmospheric carbon levels been seen at this level. Natural CO2 cycles cannot account for this warming. Natural warming cycles of this Earth cannot account for how rapidly the earth is heating.IIII. Preponderance of evidenceThe evidence that suggest the reality of anthropogenic is, simply put, insurmountable. The weight of the evidence collected and scrutinized that points to the reality of anthropogenic global warming, when compared to the evidence presented against is like comparing the weight of a blue whale to the weight of a vole. Consider the following famous "Powell Charts."Peer reviewed climatology articles 1991-2012 Peer reviewed studies 2013 This isn't simply just scientists saying "I think anthropogenic global warming is real!"This is thousands of experts performing countless experiments, collecting endless data that they, as experts, have critically analyzed, and have found that the data demonstrates definitively that man-made global warming exists, and is the driving force behind climate change.SummaryThere is no room in the scientific community for climate change deniersSources in comments.

Global Warming is not significantly affected by human activity Resolved: That Global Warming is not significantly affected by humans I thank the opponent for the debate challenge. As the opponent has not defined any terms, the definition of the terms shall go as follows: Global Warming: Noun The unequivocal rise of the global average temperature; also attributed to the unpredictable climate in the world. [1] Significantly: Adverb In a sufficiently great or important way as to be worthy of attention. [2] Humans: Noun Mankind, homo-sapiens, Affected: Adjective Influenced or touched by an external factor. [2] Since this debate resolution is a normative resolution, the Burden of Proof is shared. For the opponent to win, he has to prove that humans have almost no responsibility in causing global warming. With this said, the introduction and the proof that global warming exists shall be shared first, as this debate cannot go on with the assumption that it exists, as assumptions are inherently detrimental. Axiom One: Global Warming Necessarily Exists Global warming is no longer a possibility, but it is indeed a necessity. There has been an increase of 0.8 degrees Celsius in the last 100 years, with 0.7 degrees Celsius of this increase happening in the last 30 years [3]. From 1880, the temperature of the world was recorded via NASA meteorological stations; this data proved vital in identifying a change in temperature. From 1980 upwards, one can see a very high increase in the mean temperature of the world; the running average of global temperature from 1980 has increased by almost 100%. This graph, compiled by NASA GISS from data provided by many sources, confirms that Global Warming necessarily exists, as can be seen via the sharp increase of the running average from 1980. Global Warming exists; there is no doubt. Then what causes Global Warming? It is us, humans, that cause Global Warming. Proposition One: Carbon Dioxide Release from Multiple Sources Global warming has been allegedly caused by an excess of Co2 release from the ocean and multiple other sources. Accordingly in 2000, 29.5% of Co2 emissions came from power stations, 20.6% from Industrial Inputs/Outputs, 11.3% from residences and 9.1% from land use/biomass. [4] In 2008, 8.37 billion tons of Co2 was released from multiple of human based sources. However, one might object; “what’s wrong with the increase in release of Co2?” Quite simply this; the sun emits ultraviolet radiation and light into the earth as energy. The earth absorbs and the re-emits some of this energy as infrared radiation back. However, greenhouse gases on the atmosphere absorb this temperature and releases it in arbitrary directions; henceforth, the earth is 33 degrees warmer than what it should have been, causing life to exist on this planet. However, this 33 degrees Celsius is the equilibrium; for it to go lower would be positive feedback, as the equilibrium could easily be restored in a short period of time, but for it to go higher would make this positive feedback and would threaten to turn our planet into a “Venus” like planet (not suitable for life). This positive feedback is more dangerous than the negative feedback, for it requires intense study of the origins of the causes. [5][6] The causes of this release are the anthropocentric human lifestyle. To support our life, we humans have taken means to extract resources from mother nation in a Machiavellian manner. Humans are egoistic, hence the development of Capitalism and the government. From the following graph, we can see a correlation; from 1980, Co2 release sprouted and so did gas production. If oil production is increasing, then clearly oil is also in demand; the burning of 4 liters of oil creates a shocking 8 kg of Co2. [7] 73 million kg of Co2 is henceforth released by the increase consumption of oil/diesel fuels; with these increases of Co2 emissions from fuel burning and usage alone, we can see that there is no reason to believe that humans are not causing this increase in Co2 emissions. This graph also shows how the Industrial Revolution, in around 1840, has caused the dramatic rise of Co2 concentration. The Industrial Revolution was the basis of all industries; it revolutionized many industries and increased outputs via machinery. However, the Industrial Revolution had its basis on coal and electricity. Apart from natural gases, coal is also a huge factor in Co2 release. The usage of anthracite coal releases 920g of Co2 per kW/h, whilst the usage of lignite coal releases 990g of Co2 per kW/h. Coal is burnt for one reason only; to supply us with the electricity that runs this computer, this website, and this world. In South Africa, for example, 74% of all Co2 emissions is caused by coal burning; it would be doubtful that if humans were present, this figure would not be present. [8] As stated via the first graph of this proposition’s defense, the correlation between oil production and Co2 released is further supported by the fact that burning fuels for human usage causes the increase in the release of Co2. Proposition Two: Deforestation This second proposition is based upon two fundamental premises. 1. Trees absorb Co2 and release oxygen 2. Forest Fires increases Co2 release The first of these two premises is based upon the fact that trees absorb Co2 and release oxygen. This process is called photosynthesis; trees, for so long, have sustained our life through this process. A single tree can absorb 21kg of Carbon Dioxide! That is enough to absorb the burning of 12 liters of oil! “Only if there were more trees” one would say. [9] The existence of trees means that excess Co2 could be processed and could possibly be eradicated in large amounts. However, deforestation has created a very sad and woeful dilemma for us; we are releasing more Co2 than eve, and yet we are cutting down the mechanisms that fate gave us to counter this Co2 release. It is estimated that 20% of all Co2 in the atmosphere right now would have been absorbed and would be non-existent if it weren’t for massive deforestation. [10] The second of these premises are based upon the mere process of global warming; the warmer the temperature, the more likelihood of fires turning from small fires to huge fires. Forest fires are one of the most feared disasters in the world. Forest fires, apart from killing a plethora of citizens, can release as much Co2 as cars do. A study was released that demonstrates that in these United States of America, 290 million tones of Co2 was released due to forest fires, which is 4-6% of the entirety of Co2 released during that year. [11] Humans, due to their anthropocentric interests, have caused forest fires to appear more often due to the reckless burning of grass, wood, and other resources can cause forest fires. There is also a considerable amount of cases where forest fires started with someone carelessly dropping a cigarette on the forest grounds. This evidence shows that humans are highly responsible for the creation of global warming; we are deferring how we absorb Co2 as well as releasing more of it. This is significant in such a manner that this issue cannot be ignored. Our planet will become Venus in the following years if this issued is not cared too. The resolution is therefore negated. Citations: [4]http://en.wikipedia.org... [11] http://www.livescience.com... [10] http://en.wikipedia.org... [3]http://en.wikipedia.org... [1] Wikipedia [2] Oxford Dictionary [6] http://climate.nasa.gov... [8] http://www.iea.org... [9] http://www.arborenvironmentalalliance.com... [7] http://www.eia.gov... [5] http://www.skepticalscience.com...

Global Warming is primarily caused by humans I accept your challenge. I accept the conditions unto which it has been made. Begin when ready.

global climate change is human caused Humans are causing the rise in clobal temperature, which if not stopped will result in global warming.

Is Human Activity an addition to increased Global Warming/Climate Change Thank you for your reminder that I have not given a single evidence that goes against your case. To fight against a popular belief, the odds have been against me from the beginning. You have certainly won if this was a popularity contest. What I want to say in my previous argument was that you have not put matters into perspective. Here are my facts which I hope can put matters into perspective: A)Dinosaurs that roamed the Earth 250 million years ago knew a world with five times more carbon dioxide than is present on Earth today, researchers say, and new techniques for estimating the amount of carbon dioxide on prehistoric Earth may help scientists predict how Earth's climate may change in the future B) CO2 is not the only driver to climate change; atmospheric CO2 levels have reached spectacular values in the deep past, possibly topping over 5000 ppm in the late Ordovician around 440 million years ago. C) The global concentration of carbon dioxide in the atmosphere " the primary driver of recent climate change " has reached 400 parts per million (ppm) for the first time in recorded history, according to data from the Mauna Loa Observatory in Hawaii. D) Solar activity also falls as you go further back. In the early Phanerozoic, solar output was about 4% less than current levels. The combined effect of sun and CO2 matches well with climate. E) I hope you can agree that the Sun is an independent system of the Earth. Therefore, whatever we do on earth do not affect the sun's activities. My Analysis of the situation: [A] means that the earth is capable of sustaining life and handling CO2 level that is 5 times more than what we have today. [B] & [C] support the CO2 level is 10 times more than now prior to the dinosaurs, which roughly supports [A] [D] supports that it is the combined effect of sun and CO2 that contributes to the climate change. You can see that even if we increase our current output, it would take a long time to create CO2 level that is 5 times more than what we have now. Even at that level, earth can sustain life like dinosaurs. Therefore, human activity does contribute to climate change in the time scale of a 100 year, but to put in into perspective, over the time scale that date back to the beginning of life, human contributed CO2 level doesn"t affect life all that much. The sun would probably be a greater contributing factor than us human. Of course, with that said, even if we are not the major contributing factor, it is always our responsibilities to do less harm to others and to the nature" even though the sun would have killed us anyway in the end.

Mankind Is the Main Cause of Global Warming Extend all arguments.

Humanity is the main cause of global warming. Yes, I agree with Pro's sources in Round 5 that list all of the ways in which human activity plays a role in affecting global climate. Unfortunately, Pro failed to acknowledge the issue of "Attribution of Recent Climate Change" which I brought up in Round 4. Without doing so, it is impossible to conclude that ". .. Humanity is the Main Cause of Global Warming" as Pro has done. To further bolster my argument, I will reference the 376 page scholarly book (published in 2015) "Climate Change, Multidecadal and Beyond" . https://books.google.ca... which flatly states outright in the introduction "Many questions concerning the nature and causes of climate variability on the multidecadal time scale are still unresolved. ". This book also references a Technical Summary of the IPCC's Fourth Assessment Report which acknowledges "Difficulties remain in attributing temperature changes at smaller than continental scales and over time scales less than 50 years. " (Solomon et al. , 2007). While generalist websites for the public (such as the ones referenced by pro) may ignore the issue of attribution, clearly scholars and climate scientists cannot and do not. The book I referenced demonstrates that scientists are working very hard on the attribution issue, and may resolve it in the near future thanks to ever improving technology, statistics and modeling. However, being that the world's top scientists have not resolved the issue of climate change attribution, it is far too premature for "pro" declare a victory or a conclusion that humanity is the "main" cause of climate change (based on the information contained in generalist websites), especially in the context of a Multidecadal view. I was very much hoping that Pro would address the issue of 'Attribution of Recent Climate Change' which I introduced in Round 4.

HUMANS ARE RESPONSIBLE FOR GLOBAL WARMING WE RE RESPONSIBLE FOR ITS ACCELERATION...DEFORESTATION FOR THE CONSTRUCTION OF BUILDINGS ....UNCONTROLLED POLLUTION

Human activities are the main cause global warming. i'd like to refute my opponents points and then return back to defending mine. regarding my opponents first point, his point simply stated that humans pollute the earth. duh. of course human pollute the earth but this evidence is not conclusive enough to state that they are the main cause of the earth's rising temperature. we must look to a far greater source of carbon and other greenhouse gases: the earth itself. trees, volcanoes, and cosmic rays all cause the atmosphere to trap in heat. and there is far more carbon being produced by these natural occurances than humans as proven by avery's and singer's studies. to place this blame of such great magnitude on humans is proposterous. and also, no where in any research could i find a stat that humans cause "more than 50%" of global warming. in my opponents second point, he simply stated that people believe in the greenhouse gas theory. although this is true, i have evidence to support the other side. recently a petition was circulating around the oregon institute of science and medicine of over 17,000 highly qualified scientists who believe that humans releasing carbon dioxide and other greenhouse gases will not cause a catastrophe in the foreseeable future. in response another petition had been created recieving only 2,600 signatures stating that humans are causing this change. signatures for this survey consisted of only 10% scientists and of that 10%, only 1% were climatologists. and also a recent court case in britain ruled that "an inconvenient truth" could not be shown in school because it was ruled non-factual. my opponent states that the UN agrees with him that humans are the cause of global warming but if you gander at his debate history, he is involved in a debate that states the UN is a bad organization. a little hypocritical, huh krebs? :) moving to my side of the argument my opponent showed no means of proving that global warming is not happened because of the earth's dawning ice age so this point still stands. i clearly prove that because we are coming up on an ice age, this is the culprit of rising temperatures and not humans my second point covered fossil fuel emissions which is most commonly named for causing global warming and i disproved this and stated that rising temperature actually causes rising CO2 levels and not the other way around thank you.

Scientists have no proof that humans are responsible for a significant amount of global warming. "Certainly not in comparison to the amounts of CO2 that is created naturally on this planet." Well, the major natural emissions of CO2 come from volcanoes. Volcanoes are estimated to be releasing 200 million tons of C02 annually. Now, compare that to the estimated 26.8 BILLION TONS released by humans annually. That is about 130 times greater than the amount emitted by volcanoes. (http://hvo.wr.usgs.gov...- the US Geological Survey.) Since the start of the industrial revolution, there has been a climb in carbon dioxide concentrations in the atmosphere of about 280 ppm to 364 ppm. This clearly is larger than what is created naturally. "For example, if we could prove that humans and human activity give of 2% of the world's CO2, then we would have some information to act (or not act depending on whether one considers that a significant amount)." Well, as I have just shown that humans are the greatest contributers to CO2 output, now we have some information to act on. 27 billion tons annually is definitely a significant amount. "So far no one has been able to prove to what degree we contribute to global warming. " To what degree? How far does it need to go before it is considered a "degree"? 400,000 miles of the Arctic ice sea have melted, roughly the size of Texas. If we continue current projections, by 2030, there will be no glaciers left in glacier national park. Hurricanes and tropical storms have increased estimated 75% increase in category 4 and 5 hurricanes since 1970 according to a study done by MIT. ( http://www.nature.com... ) "Well, since it can be proved that earth has gone through many large temperature swings, and long before humans were around, there would be a very strong case for "natural" global warming (and cooling)." Well, it would be a strong case for "natural" global warming....except for the fact that no natural causes have been found, and humans are emitting enough CO2 into the air to cause a definite and serious heating effect.

Anthropogenic Global Warming is a Threat Climate reacts to whatever forces it to change at the time. We must ask why climate has changed in the past. There are many ways the Earth's climate can be affected. Something such as the sun getting brighter causing the planet to receive more energy and warms. When there are more greenhouse gases in the atmosphere the planet warms. It's true in the past climate change was caused by natural forces, but this doesn't mean we cannot cause climate change. It's like saying humans can't start brushfires because they happen naturally. In this day we are adding greenhouse gases to the atmosphere at an increasingly rapid rate. During the Cretaceous period submarine volcanic CO2 emissions were released into the atmosphere at rates high enough to cause atmospheric CO2 concentrations in excess of 1,000 ppm. This CO2 buildup also resulted from rapid sea-floor spreading related to the breakup and drifting apart of the Earth’s continents[1]There has been evidence that suggests that the Medieval Warm Period was warmer than today in some parts of the globe like the North Atlantic. However, evidence also suggest that in some places were much cooler than today, such as the tropical pacific. When the warm places were averaged out with the cool places, it is clear that the overall warmth was probably similar to the early mid 20th century warming. Since that early century warming, temperatures have risen well-beyond those achieved during the Medieval Warm Period across most of the Globe. This has been confirmed by the National Academy of Sciences Report on Climate Reconstructions[2]. Further evidence suggests that even in the Northern Hemisphere where the Medieval Warm Period was the most visible, temperatures are now beyond those experienced during Medieval times.[3] Here is the temperature pattern of the MWP vs today. The carbon plants collect from the CO2 in the air forms their tissues - roots, stems, leaves, and fruit. These tissues form the base of the food chain, as they are eaten by animals, which are eaten by other animals, and so on. As humans, we are part of this food chain. All the carbon in our body comes either directly or indirectly from plants, which took it out of the air only recently. Therefore, when we breathe out, all the carbon dioxide we exhale has already been accounted for. We are simply returning to the air the same carbon that was there to begin with. Remember, it's a carbon cycle, not a straight line.C02 does help plants, yet an abundance of it is harmful. Here is only 2 examples out of many.1.Too high a concentration of CO2 causes a reduction of photosynthesis[4] in certain of plants. There is also evidence from the past of major damage[5] to a wide variety of plants species from a sudden rise in CO2. Higher concentrations of CO2 also reduce the nutritional quality of some staples, such as wheat[6]. 2. As is confirmed by long-term experiments[7], plants with exorbitant supplies of CO2 run up against limited availability of other nutrients. These long term projects show that while some plants exhibit a brief and promising burst of growth upon initial exposure to C02, effects such as the "nitrogen plateau" soon truncate this benefit Please see the video on the right for more information http://www.youtube.com...There is evidence that shows humans are the cause of global warming Here is the first 5 of "10 Indicators of a Human Fingerprint on Climate Change"[8] 1.Humans are currently emitting around 30 billion tonnes of CO2 into the atmosphere every year[9]. Of course, it could be coincidence that CO2 levels are rising so sharply at the same time so let's look at more evidence that we're responsible for the rise in CO2 levels. 2.When we measure the type of carbon accumulating in the atmosphere, we observe more of the type of carbon that comes from fossil fuels [10]. 3.This is corroborated by measurements of oxygen in the atmosphere. Oxygen levels are falling in line with the amount of carbon dioxide rising, just as you'd expect from fossil fuel burning which takes oxygen out of the air to create carbon dioxide [11]. 4.Further independent evidence that humans are raising CO2 levels comes from measurements of carbon found in coral records going back several centuries. These find a recent sharp rise in the type of carbon that comes from fossil fuels [12]. 5.So we know humans are raising CO2 levels. What's the effect? Satellites measure less heat escaping out to space, at the particular wavelengths that CO2 absorbs heat, thus finding "direct experimental evidence for a significant increase in the Earth's greenhouse effect". [13][14][15]This shows that temperature is cyclic.A natural cycle requires a forcing, and no known forcing exists that fits the fingerprints of observed warming - except anthropogenic greenhouse gases. The Resolution is affirmed. Sources[1] Caldeira, K., and Rampino, M.R., 1991, The mid-Cretaceous superplume, carbon dioxide, and global warming: Geophysical Research Letters, v. 18, no. 6, p. 987-990.[2]http://books.nap.edu...[3]http://www.ncdc.noaa.gov...[4]http://resources.metapress.com...[5]http://www.pnas.org...[6]http://www.sciencemag.org...[7]http://www.nature.com...[8]http://www.skepticalscience.com...[9]http://cdiac.ornl.gov...[10]http://www.esrl.noaa.gov...[11]Ibid[12]http://www.sciencemag.org...[13]http://www.nature.com...[14]http://spiedl.aip.org...[15]http://www.eumetsat.eu...

Climate Change is driven by human CO2 emissions I am assuming that I will be arguing that humans are a major cause to global warming increases with C02 emissions. My first point, is that C02 emissions are scientifically proven to be a mjor leading cause in the rise of global climate changes, IE Global warming. "Global warming is caused by the emission of greenhouse gases . 72% of the totally emitted greenhouse gases is carbon dioxide (CO2), 18% Methane and 9% Nitrous oxide (NOx). Carbon dioxide emissions therefore are the most important cause of global warming. CO2 is inevitably created by burning fuels like e. g. oil, natural gas, diesel, organic-diesel, petrol, organic-petrol, ethanol. " . http://timeforchange.org...From the year 1991 to the year 2005, There has been a significant increase in harm done to the atmosphere, mainly due to C02 emissions. See picture. "This graph best represents what is taking place world wide. Recent investigations have shown that inconceivable catastrophic changes in the environment will take place if the global temperatures increase by more than 2° C (3.6° F). A warming of 2° C (3.6° F) corresponds to a carbon dioxide (CO2) concentration of about 450 ppm (parts per million) in the atmosphere. As of beginning of 2007, the CO2 concentration is already at 380 ppm and it raises on average 2 - 3 ppm each year, so that the critical value will be reached in approximately 20 to 30 years from now. "The point here, is that C02 emissions DO harm the atmosphere. My opponent cannot prove that it doesn't because statistically, scientifically, and factually, the evidence stacks up. What has happened recently? "Carbon dioxide (CO2) is the primary greenhouse gas emitted through human activities. In 2010, CO2 accounted for about 84% of all U. S. greenhouse gas emissions from human activities. Carbon dioxide is naturally present in the atmosphere as part of the Earth's carbon cycle (the natural circulation of carbon among the atmosphere, oceans, soil, plants, and animals). Human activities are altering the carbon cycle--both by adding more CO2 to the atmosphere and by influencing the ability of natural sinks, like forests, to remove CO2 from the atmosphere. While CO2 emissions come from a variety of natural sources, human-related emissions are responsible for the increase that has occurred in the atmosphere since the industrial revolution. " The carbon Dioxide emitted is MAN MADE. The things we use everyday, emit vasts amounts of carbon dioxide. Coal, natural gas, and oil are prime examples of things that we humans use daily that attribute to harsh environmental conditions. To be more specific, here is a graph that shows details on what things most commonly used to emit human made Carbon Dioxide. The information cited above is from the Environmental Protection agency, and backed from a government based site. . http://www.epa.gov... Without tryin to sounds to repetive, I don't really know how else to argue this point. It is man made. There are tons of statistics, data, analytics, etc, that I could continue citing that prove the point here. Also, I am not entirely sure what my opponent is going to attempt to argue. In his first round, he says: "CON argues that global warming is primarily controlled by human emissions" What exactly do you mean by human emissions? For example I am arguing what you said to argue, however I am also arguing that C02 emissions are man made. I ask this because I don't want to have any confusions. None-the-less I have uphelp the BOP in this debate so far, as asked in round 1. I ask that any further clarifications on the topic be made in the following rebuttal, and I will respond in the like.

global warming is cause by humans Scientists have concluded that most of the observed warming is very likely due to the burning of coal, oil, and gas. This conclusion is based on a detailed understanding of the atmospheric greenhouse effect and how human activities have been tweaking it. At the same time, other reasonable explanations, most notably changes in the Sun, have been ruled out. The atmospheric greenhouse effect naturally keeps our planet warm enough to be livable. Sunlight passes through the atmosphere. Light-colored surfaces, such as clouds or ice caps, radiate some heat back into space. But most of the incoming heat warms the planet's surface. The Earth then radiates some heat back into the atmosphere. Some of that heat is trapped by greenhouse gases in the atmosphere, including carbon dioxide (CO2). Human activity--such as burning fossil fuels--causes more greenhouse gases to build up in the atmosphere. As the atmosphere "thickens" with more greenhouse gases, more heat is held in. Fossil fuels such as oil, coal and natural gas are high in carbon and, when burned, produce major amounts of carbon dioxide or CO2. A single gallon of gasoline, when burned, puts 19 pounds of carbon dioxide into the atmosphere.

The human effect on global warming is significant. (Paraphrased from http://www.debate.org...) I'm not sure how well I worded the debate resolution, so I will explain further. This is a scientific debate about whether humans are driving global warming and whether it is a problem. Not all evidence has to be inherently scientific, but all evidence should give reasons to believe that the human effect on global warming is significant (PRO) or insignificant (CON). Definitions Human effect: Effect caused by unnatural human actions; this includes sources such as factories and power plants but excludes sources such as natural respiration. Global warming: an increase in the earth's average atmospheric and oceanic temperature that causes corresponding changes in climate and that may result from the greenhouse effect. (dictionary.com) CO2: Carbon dioxide. AGW: Anthropogenic global warming; global warming caused by human activities. ======================== Contention 1: Basic Scientific Argument ======================== (I have purposely left out some information; I cannot fill all the holes in 8000 characters, and will therefore only fill the holes that my opponent pokes at.) The sun radiates electromagnetic waves onto the earth. They pass through the atmosphere, but are absorbed by the ground. When molecules on the ground absorb the electromagnetic radiation, they then re-emit it as infrared radiation. Infrared has a longer wavelength, so some atmospheric gases, called greenhouse gases ï¿½€" namely water vapor, CO2, and methane (CH4) ï¿½€" absorb it and turn it into thermal energy (a.k.a. heat). This traps heat, causing the earth's temperature to increase. Because of the greenhouse effect, the more greenhouse gases there are, the hotter it gets. This effect isn't much like a greenhouse, but I will nonetheless use the term. For hundreds of thousands of years, CO2 levels remained in the 180 to 300 ppm (parts per million) range [1]. But as of 2007, CO2 levels were at 390 ppm [2]. The environment was relatively stable for hundreds of thousands of years, so why the sudden change? Human emissions can only be responsible. Humans have been emitting CO2 in vast quantities since the mid-70's: our cars emit it, our factories emit it, even our homes emit it. ======================== Contention 2: Scientific Consensus ======================== It is important to remember that science is not a democracy. But if nearly all scientists agree on something, it is probably correct. And nearly all scientists support AGW. I: Scientific Societies Many scientific societies have advocated for AGW. At this time, it is important to remember that scientific societies are not advocacy groups. But these societies found AGW so important that they felt they had to endorse it. The national scientific societies of 21 countries have endorsed AGW: Australia, Belgium, Brazil, Caribbean, Canada, China, France, Germany, India, Indonesia, Ireland, Italy, Japan, Malaysia, Mexico, New Zealand, Russia, South, Africa, Switzerland, United Kingdom, United States [3]. The following societies have also endorsed AGW: Network of African Science Academies, National Research Council, European Science Foundation, World Meteorological Organization, Federation of American Scientists, American Meteorological Society, American Association for the Advancement of Science [4]. This is far from a complete list, but is meant to give an idea of how many scientists support AGW. This list represents hundreds of thousands of scientists. II: Peer-Reviewed Papers Perhaps more important than the endorsement of scientific societies is peer-reviewed papers. In 2004, Science magazine conducted a search for scientific papers on the topic of global warming [5]. They searched through all papers with the keywords "climate change", for a total of 928 scientific articles. Here is a quote from [5]: {quote} The 928 papers were divided into six categories... Of all the papers, 75% fell into the first three categories, either explicitly or implicitly accepting the consensus view; 25% dealt with methods or paleoclimate, taking no position on current anthropogenic climate change. Remarkably, none of the papers disagreed with the consensus position. Admittedly, authors evaluating impacts, developing methods, or studying paleoclimatic change might believe that current climate change is natural. However, none of these papers argued that point. This analysis shows that scientists publishing in the peer-reviewed literature agree with IPCC, the National Academy of Sciences, and the public statements of their professional societies. Politicians, economists, journalists, and others may have the impression of confusion, disagreement, or discord among climate scientists, but that impression is incorrect. The scientific consensus might, of course, be wrong. If the history of science teaches anything, it is humility, and no one can be faulted for failing to act on what is not known. But our grandchildren will surely blame us if they find that we understood the reality of anthropogenic climate change and failed to do anything about it. Many details about climate interactions are not well understood, and there are ample grounds for continued research to provide a better basis for understanding climate dynamics. The question of what to do about climate change is also still open. But there is a scientific consensus on the reality of AGW. Climate scientists have repeatedly tried to make this clear. It is time for the rest of us to listen. {/quote} *** I thank my soon-to-be opponent and look forward to a fun debate. *** References [1] http://www.newscientist.com...... [2] http://www.newscientist.com...... [3] http://logicalscience.com...... [4] http://www.aaas.org...... [5] http://www.sciencemag.org......

Global warming (full resolution in debate) Thanks for a swift reply. I. WHAT IS A GREENHOUSE GAS? This was an observation as my partner points out. Conceded to both sides.II. THE GREENHOUSE EFFECT My partner's claim is that CO2 is very minute scale in the atmosphere and it really doesn't effect us that much. However, let's see how much CO2 can hurt us. This graph is from NASA and it shows the relationship between CO2 and climate change: [1] The current level of CO2 is 380 parter per million. So, my partner brought up a good question: IF carbon dioxide makes up only a minute portion of the atmosphere, how can global warming be traced to it? And how can such a tiny amount of change produce such large effects? Pieter Tans from NOAA's Earth system Research Labratory provides this answer: [2] "The earth's surface absorbs visible radiation from the sun, which causes heating. At the same time the surface and the atmosphere emit infrared radiation back to space, which produces cooling. Our eyes cannot see infrared radiation but we can feel how our skin absorbs it when we are standing next to a hot object without touching it. Over a long period the earth's surface temperature will remain approximately constant because the amount of heat absorbed as visible light is equal to the amount emitted as infrared light. Nitrogen, oxygen and argon together comprise more than 99 percent of the atmosphere. None of these three gases absorb either visible or infrared light; both types penetrate the entire atmosphere. It is as though, when it comes to the absorption and emission of light, the atmosphere's three main components do not exist!" So, what is happening is as the surface of the earth absorbs visible radiation from the sun, it causes heating. Simultaniously, the surface and the atmosphere emit infrared radiation back into space which produces cooling. Although Nitrogen, Oxygen, and Argon together make up 99% of the atmosphere, these gasses do not absorb visible or infrared light thus penetrating the entire atmosphere. Consequently, the greenhosue gasses take their toll. He continues: "The next most abundant gases--water vapor and carbon dioxide--do absorb a portion of the infrared heat radiated by the earth's surface, thereby preventing it from reaching space. Instead of dissipating into space, the infrared radiation that is absorbed by atmospheric water vapor or carbon dioxide produces heating, which in turn makes the earth's surface warmer. This is known as the greenhouse effect and without it our planet's surface would likely be frozen, like Mars. The heat absorbed by water vapor and carbon dioxide is shared with all the nitrogen, oxygen and argon, because the latter molecules are always bumping into water vapor and carbon dioxide as they mix in the atmosphere. This effect makes the atmosphere act somewhat like a blanket that becomes thicker when amounts of water vapor, carbon dioxide and other greenhouse gases, such as methane and nitrous oxide, increase. The top of the blanket remains cold and continues to emit about the same amount of infrared to space but below the blanket it gets warmer because it is more difficult for the heat to rise to the top. The heating effect of extra carbon dioxide, methane, nitrous oxide and many other minor gases can be calculated with confidence based on the absorption properties that have been measured carefully in the laboratory. Currently, the total heating produced by the increases of all long-lived greenhouse gases (excluding water vapor) since preindustrial times is equal to about 1 percent of all solar radiation absorbed at the surface. The effect would be somewhat similar if the sun had started to shine 1 percent more brightly during the 20th century." Next, 16kadams claims that human CO2 are too tiny to matter; less than 5%. However, this once more is not entirely accurate. From the graph and from ice cores, we see that CO2 in the atmosphere remained stable between 180-300 ppm for the past 500,000 years [3]. In recent centuries since we started contributing to CO2, it has risen vastly to over 380 ppm. What does all this show? it shows that humans do play an important factor in the contribution to CO2. III. PROOF I cited 3 proofs to show that humans are contributing mainly to global warming: (1) Human finger print on CO2; (2) Nature alone cannot account for the changes that we see; and (3) Lower-level atmosphere — which contains the carbon load—is expanding. 1. CO2 does trap heat, but as mentioned:See above as I have refuted what my partner stated above.=======================>REFUTATIONS TO CON'S R1<==================================Natural cycles Noted above.Problems with the GH theory My partner is correct in saying that water vapor is the most abundant greenhouse gas; however, CO2 still plays the most important role in greenhouse gas. We do not want to look only at the abundance of the greenhosue gas; but also its influence. The Union of Concerned Scientists notes: [4] "CO2 has caused most of the warming and its influence is expected to continue. CO2, more than any other climate driver, has contributed the most to climate change between 1750 and 2005.[1, 2, 3] The Intergovernmental Panel on Climate Change (IPCC) issued a global climate assessment in 2007 that compared the relative influence exerted by key heat-trapping gases, tiny particles known as aerosols, and land use change of human origin on our climate between 1750 and 2005.[3] By measuring the abundance of heat-trapping gases in ice cores, the atmosphere, and other climate drivers along with models, the IPCC calculated the “radiative forcing” (RF) of each climate driver—in other words, the net increase (or decrease) in the amount of energy reaching Earth’s surface attributable to that climate driver. Positive RF values represent average surface warming and negative values represent average surface cooling. CO2 has the highest positive RF (see Figure 1) of all the human-influenced climate drivers compared by the IPCC. Other gases have more potent heat-trapping ability molecule per molecule than CO2 (e.g. methane), but are simply far less abundant in the atmosphere and being added more slowly."Here is a graph from the same source to note the climate influence of the different greenhouse gasses. Out of room/time. Good luck! ________________________________Sources 1. Courtesy of NASA at URL: http://climate.nasa.gov...;2. Scientific American (20060 http://www.scientificamerican.com... 3. http://www.newscientist.com...;4. http://www.ucsusa.org...;

Mankind Is the Main Cause of Global Warming Consider this my acceptance.

Resolved: Human Activity Is a Significant Factor in Global Warming on Planet Earth. The voting floor is set at 1500. If accepted without permission, Pro automatically wins the debate. ______________________________________________________________I will add in definitions to prevent semantics arguments from arising. DEFINITIONS Human activity: Activity associated with or caused by humans. Global Warming: The state of which the Earth's temperature progressively and abnormally rises, which is attributed to the Greenhouse Effect that is caused by increased levels of carbon dioxide, other greenhouse gases, and pollutants in general. REMEMBER, THIS REFERS TO THE WARMING IN THE PAST 115 YEARS. Planet Earth: The 3rd closest planet from the Sun in the solar system, which is known for being the only known planet that currently sustains life. Significant: Sufficiently great or important to be worthy of attention as viewed by the judges with statistically large sample sizesRules:1. Breaking any rules (except for rules related to voting) will result in automatic forfeiture of all seven points to the opponent. If both sides break the rules, votes will be placed as normal. Invalid votes will result in reporting the vote.2. No semantics.3. No forfeiture.4. No Ad Hominem OR mere insults5. Plagiarism is absolutely prohibited. 6. All arguments must be contained within the character limit. Words or characters on videos, soundtracks or pictures are exempted and do not apply. Sources are also exempted.7. (Branches off from above rule) Extra arguments in the comments section are forbidden.8. The debate must be followed under the below structure:Round 1: Acceptance. Round 2: Opening arguments and Constructive Case, NO REBUTTALSRound 3: More arguments, Rebuttals and Strengthening of original caseRound 4: Final arguments, Clarification of case, counter-rebuttals and rebuttalsRound 5: Clarification of case, Counter rebuttals, rebuttals, closing statements, NO NEW ARGUMENTS9. No trolling or spamming.10. No cheating (Gish-gallop, asking for votes in your favor, etc. )11. Accepting without permission is a forfeiture of the debate.12. Kritiks of the topic are not accepted. As shown, first round is acceptance. I look forward to a fun and intriguing debate!

global climate change is human caused "It is also true that it has recently gone up more in the 20th century then it has before." -According to the EPA: "Records from land stations and ships indicate that the global mean surface temperature warmed by between 1.0 and 1.7ï¿½F since 1850 (see Figure 1). These records indicate a near level trend in temperatures from 1880 to about 1910, a rise to 1945, a slight decline to about 1975, and a rise to present (NRC, 2006)." Now, the problem with this is that there was not a decline, rather a rise, in CO2 emissions between 1945-1975, so it is nearly impossible to pin the blame on any one factor, particularly humans. The EPA also states that: "Between roughly 900 and 1300 AD, evidence suggests Europe, Greenland and Asia experienced relative warmth. While historical accounts and other evidence document the warmth that occurred in some regions, the geographical extent, magnitude and timing of the warmth during this period is uncertain (NRC, 2006). The American West experienced very dry conditions around this time." This all occured BEFORE the industrial revolution, and before humans could possibly have any significant effect on global greenhouse gases. According to the EPA, though there is confidence within the scientific communit, there is not enough evidence to assign human fault in recent climate change: "Present evidence suggests that temperatures at many, but not all, individual locations were higher during the past 25 years than any period of comparable length since A.D. 900. However, uncertainties associated with this statement increase substantially backward in time." That's just referring to the last 25 years, and discounting the drop in climate between 1945-1975. "Why do you think that is if not because of the constant burning of fossil fuels humans burn daily." -Well, thanks for asking what I think. I think the Earth has a natural cycle of warming and cooling. I believe the Eearth has natural elements which control the percentages of greenhouse gases in it's atmosphere which regulate the temperatures between cooling periods (ice ages), warming periods (like now), and stable periods. There is enough evidence to suggest that humans are a contributing factor in a significant rise in the amounts of greenhouse gas emissions in the atmosphere, but the sharp rise in greenhouse gases in the atmosphere does not coincide with the slight rise in global mean temperature. "This lets off too many gases into the atmosphere which causes the green house effect which results in Global Warming." -The "greenhouse effect" is a GOOD thing. Any planet with an atmosphere has a "greenhouse effect"... otherwise the Earth would be like the moon. Global warming is also a GOOD thing. Can you imagine what the Earth would be like if it wasn't naturally insulated??? "Notice the part where it says "human activities". As you can clearly see, humans are a huge factor in Global Warming." -You didn't prove this, you simply stated this. Even if you were right, you are now contradicting your original statement. A "huge factor" is not en exclusive cause as you suggested in your statement: "Humans are causing the rise in global temperature". It also is contradictory to the entire statement: " Humans are causing the rise in clobal temperature, which if not stopped will result in global warming." Here are a few points you have failed to prove: -Humans are causing the rise in global temperature (Not true. The natural warming and cooling cycles of the planet, our current place in the warming/cooling timeline, and other natural anomalies are at least mostly responsible for any significant rise in global temperature- even by the estimates of the most staunch global warming scientists) -Humans are causing global warming. (Not true. This is completely false and impossible. Humans are not greenhouse gases, nor are we a part of the atmosphere. We are not the Sun that shines on the earth, we are not the ocean that traps and releases CO2 according to mean global temperatures, and we are not a part of hundreds of other natural factors that create the beneficial process of global warming) Now, for those of you who are too liberal and hardheaded to read a debate before voting on your own opinion- I am not saying greenhouse gas emissions should not be regulated. I am not saying that the global temperatures WON'T rise to higher levels, and I am not saying that humans do not contribute to greenhouse gas emissions. What I am saying is that the environmentalist position is misunderstood by many, and thus causes conservatives to disagree with and dismiss the issue of global warming. We must address the issues that are facts- greenhouse gases are required to promote the natural occurence of global warming. Greenhouse gases have risen by more than 38% in the past 100 years. Even if we cannot personally account for that 38% increase, we have the power to regulate further increases so that we may better aide in the stabilization of the presence of greenhouse gases so as to prevent the POSSIBILITY of an alarming increase in global temperatures. Stop the fearmongering and deal with the issues according to the facts (that applies to conservatives and liberals alike).

Global warming is not solely humans fault. Thanks for letting me debate you on this. My opponent doesn't believe we humans have caused global warming. I believe we did. Here, you can see it's very likely that humans caused it. Experts said it. http://news.nationalgeographic.com... "99 percent" is what it is, ladies and gentleman. Human activity, such as fossil fuel emissions from not-so-eco-friendly humans, agriculture, and other human-stuff has cornered our climate into the "heat zone." Our atmosphere can withstand only so much smog and exhaust from automobiles, airplanes, and boats. Smoking of cigarettes can also make a small contribution. Here are some of the biggest contributors. Source: http://www.ecobridge.org... - Carbon Dioxide from Power Plants - Carbon Dioxide Emitted from Cars - Carbon Dioxide from Airplanes - Carbon Dioxide from Buildings - Methane - Nitrous oxide - Deforestation As you can see, these projects were introduced to the Earth by man.

Resolved: Human Activity Is a Significant Factor in Global Warming on Planet Earth. Thank you, medv4380. http://www.youtube.com...http://www.youtube.com... ==Contention 1: The correlation between increase in Carbon Dioxide and global temperature== Throughout the last 650,000 years, there have been seven cycles of glacial advances and retreats, where the carbon dioxide levels abruptly increased, then gradually decreased afterward. However, in 1950, Co2 levels were at a critical level and kept on rising. As of 2014, the global Co2 levels were at an all time high of nearly 400 parts per million [1]: As we can see above, in the last 650,000 years, the Co2 levels have never grown above 300 ppm, as opposed to now, where the Co2 levels are at 400 ppm. Obviously, this abrupt growth in Co2 levels are caused by human activity, such as mass production, the use of electricity, polluting, etc. I have provided a youtube video above to show the correlation between the high Co2 levels and global temperature [2]. When both are compared, this becomes irrefutable evidence that man-made global warming exists. Note that this is all over the world, so accusations of choosing a specific area for evidence cannot be valid. In fact, as of 2013, the average global temperature was 14.6 degrees Celsius (58.3 degrees Fahrenheit), which is 0.8 degrees Celsius (1.4 degrees Fahrenheit) warmer than when the year was 1880, and 0.6 degrees Celsius (1.1 degrees Fahrenheit) warmer than the mid-20th century baseline [3][4][5]: Already, on the first contention, we have seen major evidence affirming the resolution. ==Contention 2: The cause and effect of the Greenhouse Effect and what makes it more powerful== The greenhouse effect on Planet Earth has been occurring for almost its whole life and is a natural phenomenon, since greenhouse gases such as Co2 have existed on Earth from its birth, thus heating the Earth to help sustain forms of life [6]: "To its credit, the greenhouse effect has been around long before humans began to burn fossil fuels, and it is a natural phenomenon in that makes life habitable for all living things." [6] The greenhouse effect operates when the sun's heat passes through Earth's atmosphere, heats the Earth's surface and is reflected back upward. Most of this heat is absorbed by the greenhouse gases like water vapor, Co2 and methane. Afterward, the heat is re-emited in all directions, thus starting the cycle again, continuously heating the Earth. Greenhouse gases literally act like a thermal blanket for Earth [7]: "A layer of greenhouse gases - primarily water vapor, and including much smaller amounts of carbon dioxide, methane and nitrous oxide - act as a thermal blanket for the Earth, absorbing heat and warming the surface to a life-supporting average of 59 degrees Fahrenheit (15 degrees Celsius)." [7] From this information, we can conclude that the more greenhouse gases are put into the atmosphere, the more heat from the sun is absorbed, thus creating a powerful greenhouse effect. Human actvity is causing this to happen. P1) The more greenhouse gases there are in the atmosphere, the more powerful the greenhouse effectP2) Human activity is emitting more greenhouse gases into the atmosphereC) Human activity is the cause of a more powerful greenhouse effect, and thus man-made global warming exists. To further prove this point, let us inspect Earth's neighboring planets, Mars and Venus. Mars' atmosphere is quite thin, and it's nearly completely made up of Co2. However, it is because of the low atmospheric pressure and lack of other greenhouse gases that the greenhouse effect is not at all strong and thus Mars has a frozen surface without any signs of organisms [7]. "Not enough greenhouse effect: The planet Mars has a very thin atmosphere, nearly all carbon dioxide. Because of the low atmospheric pressure, and with little to no methane or water vapor to reinforce the weak greenhouse effect, Mars has a largely frozen surface that shows no evidence of life." [7] Now, let us inspect Venus. Despite Venus' atmosphere also being almost entirely carbon dioxide, the amount of Co2 Venus contains is about 300 times as much as Mars' or Earth's. This creates a HUGELY powerful greenhouse effect, causing a temperature so high that lead could not stay solid. [7] "Too much greenhouse effect: The atmosphere of Venus, like Mars, is nearly all carbon dioxide. But Venus has about 300 times as much carbon dioxide in its atmosphere as Earth and Mars do, producing a runaway greenhouse effect and a surface temperature hot enough to melt lead." [7] This can be further proven by checking Mercury's temperature compared to Venus' temperature, even though Mercury is closer to the Sun than Venus. [8] "Venus has a very dense atmosphere made up of carbon dioxide, nitrogen, and sulfuric acid, while Mercury has a very thin atmosphere with various gases, but very little carbon dioxide." [8] Again this information is major evidence of the existence of man-made global warming. ==Contention 3: Arctic Ice and Sea Levels== It is widely agreed that melting ice from the Arctic and Antarctic and sea level rise is a sign of increasing temperatures. If I can prove that ice is definitely decreasing and that sea levels are definitely rising, then I win this contention. Here is a chart showing definite decrease in Arctic ice [9]: Here is another chart showing rising sea levels [10]: Also, recent reports state that the Arctic is losing ice three times as fast as the Antarctic is gaining ice [11][12]. "Sea ice surrounding Antarctica reached a new record high extent this year, covering more of the southern oceans than it has since scientists began a long-term satellite record to map sea ice extent in the late 1970s. The upward trend in the Antarctic, however, is only about a third of the magnitude of the rapid loss of sea ice in the Arctic Ocean." Thus, I affirm this contention. ==Conclusion== I have put forward major evidence and arguments proving the existence of man-made global warming. I have also put out evidence that the greenhouse effect does indeed exist. Thus, the resolution is affirmed. ==Sources== [1] http://climate.nasa.gov............;[2] https://www.youtube.com............;[3] http://climate.nasa.gov............;[4] http://climate.nasa.gov............;[5] http://data.giss.nasa.gov............;[6] http://earthguide.ucsd.edu............;[7] http://climate.nasa.gov............;[8] http://scienceline.ucsb.edu......[9] http://www.forbes.com......[10] http://www.nasa.gov......[11] http://www.nasa.gov......[12] https://www.youtube.com......

Mankind Is the Main Cause of Global Warming I am here going to prove to the audience and to my opposition that global warming is primarily caused by homo sapiens and is thus a characteristic of the anthropocene - a term recently created by geologists to express "the age of man." I have yet to thorougly read my opponent's arguments, so anything that I write that may seem to be a rebuttal is pure coincidence. I thank my opponent for challenging me to this debate and hope for an interesting exchange of ideas. Either he'll learn something or I will!Three Steps to Damaging the Planet (Human Style)A) Find the gases that cause the planet to warmThe following gases contribute to the greenhouse effect... (10)Feedback GasesWATER VAPOURWater vapour is a "feedback" to the climate rather than a cause of climate change. It is a greenhouse gas, but it does not contribute to a change in the greenhouse effect, rather, it changes with the temperature of the atmosphere, and thus acts as a way of telling if we're doing things right. Put simply, we on earth can't directly affect the amount of water vapour in the atmosphere, but more of it should tell us that the temperature of the planet is warming (because it evaporates. We can't heat the oceans by ourselves so we need something less direct.) and thus there's a cause - effect relationship - more CO2/Methane/etc. = Higher Temperaures = More Water VapourCausal GasesMETHANENot what you were expecting, right? But still very important. Most mammals have natural methane emissions of a kind, and this can change, so this will go into our recipe for messing with our climate. Naturally, however, it is emitted at 270 teragrams per year (9) Come back to this later.NITROUS OXIDEAlso causal to rather than resulting from a change in climate, that is, we can change how much goes into the atmosphere.CFCsThe same ones that destroy the ozone layer, this time, they're back to destroy the biosphere. I say "destroy" because CFCs are as irrefutably man - made as CO2 and Methane are not, and therefore MUST be at least one reason that the atmosphere is warming. (Since they are artificial, to say that an increase in their quantity has non - anthropogenic causes would be like saying that trees can be made of plastic).CARBON DIOXIDEThe classic greenhouse gas. Carbon dioxide is absorbed to some extent in grass and trees (photosynthesis) on a natural level, and otherwise may be released through volcanoe and major forest fires, or the combustion of organic material. This usually accounts for 750 gigatons (8) of CO2 moving through the carbon cycle every year, not including human intervention.The gases listed here under causal warm the earth through the greenhouse effect. This is not controversial, here's how it works (7)The greenhouse effect, WITHOUT human intervention (except obviously in CFCs), is caused by the above gases in the above way. Now all we have to do is add a greedy, unenlightened species and we're on our way...B) Ensure that those gases enter and remain in the atmosphere in greater (or lesser) quantities than beforeMETHANEHumans add 330 teragrams per year (9) of methane to the atmosphere every year to the 270 teragrams already entering it, mostly through methane emitted by livestock (a single modern cow emits 270 kg of methane each year), from decay in landfills and from waste treatment, not to mention the burning of biomass. If the 330 teragrams going into the atmosphere WITHOUT humans every year causes 9% of the greenhouse effect, as noted above, then that amount doubling will, of course, ENHANCE the greenhouse effect, causing - global warming. The truth is that it would be strange if it DIDN'T. There are now 2 billion cows on the planet, far more than at any point in history. They, through methane emissions, are enhancing the greenhouse effect.CARBON DIOXIDEIt has been mentioned that 750 gigatons goes through the carbon cycle every year. Humans add 29 gigatons (8) - haha, the opposition says, the amount of human emissions of CO2 every year pale in compare to how much goes through the carbon cycle! But then one takes closer look - every year, 439 gigatons are released and 450 are absorbed by plants and trees. Suddenly, the 29 gigatons becomes much more frightening, especially when one observes that carbon dioxide is now at 390 ppm (parts per million) in the atmosphere, nearly twice as high as it has been for the last 500,000 years! The higher amount of CO2 in the atmosphere is also caused, of course, by the fact that our conversion of land for agriculture has led to land with plants that absorb less CO2 (virtually all my references will say this) so that the number of gigatons absorbed (450) is decreasing whilst the 29 is increasing, resulting in idle CO2 sitting around, warming up the atmosphere - as it must as a greenhouse gas. CO2 is poisonous as well, by the way, so even if my worthy opponent and/or audience leaves this debate with their minds unchanged on the topic of anthropogenic global warming, remember that there is still reason for CO2 emissions to be curtailed!CFCsThis is an optimistic part of the human - greenhouse effect story in that we actually stopped putting CFCs into the atmosphere when we realized how awful they were for the ozone layer. Therefore we do not put CFCs into the atmosphere any more - it's like a defunct greenhouse gas, in retirement.NITROUS OXIDENO2 has an atmospheric lifetime of 121 years (11) so naturally even a small amount of nitrous coming out of your exhaust enhances global warming for years to come. And when it's 110 to 240 thousand tonnes coming from car exhaust pipes every year, you know you have a problem. Add 2 to 4 million tonnes from fertilization practices in agriculture and you have a MAJOR problem! Add to this the fact that NO2 is 310 times as powerful as CO2 as a greenhouse gas and you have a full blown nightmare.Given the endless facts and evidence presented above, it would be strange if the atmosphere was NOT warming up from human intervention. The below only affirms what should be evident. On to our third and final step.C) Watch as the planet warms or cools six degrees, the difference between now and the last ice ageIt is often mentioned that the earth's climate has change in the past, and that is most assuredly true. It is also true, of course, that the earth's climate can change in the future, and for different reasons. However, what is unique about the warming of the anthropocene is that it has happened and is happening so suddenly, more suddenly than in the past. The closest example of climate change at this speed (just 120 years since the beginning of the Industrial Revolution), obviously excluding the meteor that wiped out the dinosaurs, is the Palaeo - Eocene Thermal Maximum (13) about 55 million years ago, when the climate changed 5 to 8 degrees,that warming, of course, took several thousand years.Sources1. http://climate.nasa.gov...2. http://www.climatechangechallenge.org...3. http://environment.nationalgeographic.com...4. http://ocean.nationalgeographic.com...5. http://news.nationalgeographic.com...6. http://www.nytimes.com...7. http://www.global-greenhouse-warming.com...8. http://www.skepticalscience.com...9. http://en.wikipedia.org...10. http://raytekmalaysia.blogspot.ca...11. http://www.flickoff.org...12. http://www.epa.gov...13. http://www.guardian.co.uk...

Resolved: Human Activity Is a Significant Factor in Global Warming on Planet Earth. Same.

global warming is cause by humans first of all let me proof that global warming is happening . The 10 indicators are: Land surface air temperature as measured by weather stations. You know all those skeptic arguments about how the temperature record is biased by the urban heat island effect, badly-sited weather stations, dropped stations, and so on? This is the only indicator which suffers from all those problems. So if you"re arguing with somebody who tries to frame the discussion as being about land surface air temperature, just remind them about the other nine indicators. Sea surface temperature. As with land temperatures, the longest record goes back to 1850 and the last decade is warmest. Air temperature over the oceans. Lower troposphere temperature as measured by satellites for around 50 years. By any of these measures, the 2000s was the warmest decade and each of the last three decades has been much warmer than the previous one. Ocean heat content, for which records go back over half a century. More than 90% of the extra heat from global warming is going into the oceans " contributing to a rise in" Sea level. Tide gauge records go back to 1870, and sea level has risen at an accelerating rate. Specific humidity, which has risen in tandem with temperatures. Glaciers. 2009 was the 19th consecutive year in which there was a net loss of ice from glaciers worldwide. Northern Hemisphere snow cover, which has also decreased in recent decades. Perhaps the most dramatic change of all has been in Arctic sea ice. Satellite measurements are available back to 1979 and reliable shipping records back to 1953. September sea ice extent has shrunk by 35% since 1979. Science isn"t like a house of cards, in that removing one line of evidence (eg. land surface air temperature) wouldn"t cause the whole edifice of anthropogenic global warming to collapse. Rather, "land surface warming" is one of more than ten bricks supporting "global warming"; and with global warming established, there is a whole other set of bricks supporting "anthropogenic global warming". To undermine these conclusions, you"d need to remove most or all of the bricks supporting them " but as the evidence continues to pile up, that is becoming less and less likely. now global warming is caused by humans , proofs are - 1.Humans are currently emitting around 30 billion tonnes of CO2 into the atmosphere every year (CDIAC). Of course, it could be coincidence that CO2 levels are rising so sharply at the same time so let"s look at more evidence that we"re responsible for the rise in CO2 levels. When we measure the type of carbon accumulating in the atmosphere, we observe more of the type of carbon that comes from fossil fuels (Manning 2006). This is corroborated by measurements of oxygen in the atmosphere. Oxygen levels are falling in line with the amount of carbon dioxide rising, just as you"d expect from fossil fuel burning which takes oxygen out of the air to create carbon dioxide (Manning 2006). Further independent evidence that humans are raising CO2 levels comes from measurements of carbon found in coral records going back several centuries. These find a recent sharp rise in the type of carbon that comes from fossil fuels (Pelejero 2005). So we know humans are raising CO2 levels. What"s the effect? Satellites measure less heat escaping out to space, at the particular wavelengths that CO2 absorbs heat, thus finding "direct experimental evidence for a significant increase in the Earth"s greenhouse effect". (Harries 2001, Griggs 2004, Chen 2007). If less heat is escaping to space, where is it going? Back to the Earth"s surface. Surface measurements confirm this, observing more downward infrared radiation (Philipona 2004,Wang 2009). A closer look at the downward radiation finds more heat returning at CO2 wavelengths, leading to the conclusion that "this experimental data should effectively end the argument by skeptics that no experimental evidence exists for the connection between greenhouse gas increases in the atmosphere and global warming." (Evans 2006). If an increased greenhouse effect is causing global warming, we should see certain patterns in the warming. For example, the planet should warm faster at night than during the day. This is indeed being observed (Braganza 2004, Alexander 2006). Another distinctive pattern of greenhouse warming is cooling in the upper atmosphere, otherwise known as the stratosphere. This is exactly what"s happening (Jones 2003). With the lower atmosphere (the troposphere) warming and the upper atmosphere (the stratosphere) cooling, another consequence is the boundary between the troposphere and stratosphere, otherwise known as the tropopause, should rise as a consequence of greenhouse warming. This has been observed (Santer 2003). An even higher layer of the atmosphere, the ionosphere, is expected to cool and contract in response to greenhouse warming. This has been observed by satellites (La"tovi?ka 2006).

Humans are the main cause of global warming I will be arguing that humans are the main cause of global warming. Theefore, the burden of proof lies on me. There are no rules other than no trolling and try not to forfeit. My arguments: (copied from one of my previous debates): http://debate.org... , does not count as plagirism because it is my own work.Carbon Dioxide a. Correlation to temperature CO2 is increasing. In fact, the level of it in our atmosphere now is higher than any point in the past 800 thousand years. [1] Temperature records show that the temperature is increasing, [2] and that CO2 does have a strong correlation to the temperature,[3][2] without any apparent lag, as shown in the short term chart at [2]. b. Source of CO2 For the global warming to be caused by man, the CO2 has to be man made or have some kind of relationship to human activities. Generating electricity using fossil fuels is the largest single source of CO2 emissions in the United States, accounting for about 40% of the total CO2 emissions in 2009,[4] followed by transportation at 31% in 2010[4], and industry at 14% in 2010. [4] As you can see, humans do emit lots of CO2. Another Greenhouse Gas: Methane Methane has 25 times the effect on the atmosphere than CO2 over 100 years, [5] and it is increasing.[5] In the year 2010, methane levels in the Arctic were measured at 1850 nmol/mol, a level over twice as high as at any time in the 400,000 years prior to the industrial revolution. [5] For this to be a part of human induced global warming, it has to have a human based source, and it is. Rice fields generate large amounts of methane during plant growth. [6] Municipal solid waste also produce Methane. [6] [1]http://en.wikipedia.org...... [2]http://ossfoundation.us...... [3]http://www.grida.no...... [4]http://www.epa.gov...... [5]http://en.wikipedia.org...... [6]http://en.wikipedia.org......

Global Warming is likely impacted by humans. I'm arguing that global climate change is not impacted by humans. My reasons for believing this are as follows: 1. Earth's climate has often warmed and cooled, and the recent rise in global temperature is within the borders of the natural temperature variations that have been recorded within the past 3,000 years. A study from 2013 claimed that the rising global temperatures that have been observed in the 20th century are similar to those observed around the 11th century. 2. Changes in global temperature are generally due to variations in the sun's heat, not by human activity. The majority of the observed climate changes between the 20th and 21st centuries has corresponded with multiple solar cycles. In 2012 it was discovered that there was a strong correlation between solar radiation and temperatures in the Arctic, not by human activity.3. The receding glaciers are not a result of human activity, but rather have been growing and receding for thousands of years due to natural causes. A 2014 study of over 2,000 glaciers in the Himalayas proved that 86.6% of the glaciers were not receding. Another study claimed that receding glaciers in Antarctica were due to "atmospheric circulation changes" that caused West Antarctica to warm rapidly. 4. CO2 is not the cause. In 2003, a study showed that over the past four climactic cycles (which have occurred during the past 240,000 years) warming has not followed, but rather preceded, a rise of CO2.Of the CO2 that humans have produced between 2002-2011, about 50% has been re-absorbed by earth's "carbon sinks."Within the past 16 years there has been an 8% increase in atmospheric CO2, and still the earth has not warmed significantly. http://climatechange.procon.org...

Global Warming is likely impacted by humans. 1: Does Global Warming exist?Yes, but how do we know? The amount of evidence is compelling and indisputable from the rising global sea level to global temperature rise, warming oceans, to shrinking ice sheets. Other ways we know that global warming exists includes but is not limited to; Declining Arctic Sea, Glacial Retreat, Extreme Weather, Decreased Snow Cover, Ocean Acidification. Now that we can agree that Global Warming exists the question becomes2: Is it man made?“97 percent or more of actively publishing climate scientists agree: Climate-warming trends over the past century are very likely due to human activities.” (1)This effect made by humans is called the greenhouse effect. Defined that is “warming that results when the atmosphere traps heat radiating from Earth toward space.”(2) This is mainly caused by burning of fossil fuels like coal and oil. It is also caused by the clearing of land for agriculture, industry, and other human activities. The Intergovernmental Panel on Climate Change, which is a group of 1,300 independent scientific experts, which runs assessment reports concluded “there's a more than 90 percent probability that human activities over the past 250 years have warmed our planet.”(3)Conclusion: As we can see that Global warming exists and the experts in the field overwhelmingly conclude that Global warming is likely man made we can conclude that Global Warming is likely impacted by humans. Sources:(1) http://iopscience.iop.org...(2) http://climate.nasa.gov...(3) http://climate.nasa.gov...

Global Warming is Man-Made The sun drives of climate change The main driver of modern climate is solar activity. The energy output of the sun, called the irradiance. has been nearly constant in modern times, so that's not the cause. It is primarily the magnetic field of the sun which drives climate, and to a lesser extent the ultraviolet component of the irradiance. The magnet component varies dramatically. Norwegian scientists in the 1990's discovered that the single measure of solar activity that best predicts climate is the length of the previous solar cycle. “The most readily apparent cycle in solar activity is the cycle in sunspot activity. These solar cycles average eleven years in length, and they have ranged in length from nine years to beyond eighteen years.“ [1] The length of the solar predicts climate change as shown in the graph [2] below: The increase in CO2 is very close to exponential, so as Pro noted, AGW theory predicts a straight line temperature rise. The graph shows clearly that is not what has happened. Climate has been behaving according to solar activity. “A paper published [in 2012] in the Journal of Atmospheric and Solar-Terrestrial Physicsfinds that up to 72% of the temperature increase over the last 150 years can be explained by the length of solar cycles,” [3] The length of the solar cycle does not perfectly represent the sun effects, so it's likely that a more precise model would produce a more precise result. Cosmic rays affect cloud cover The physical theory that explains the correlation is summarized by Archibald: There are two main ways that changing solar activity affects terrestrial climate. Both have their origin in the strength of the Sun’s magnetic field. In the first route, a lower magnetic field strength results in less sunspot activity, which in turn mean less solar wind, which allows more galactic cosmic rays to get to Earth’s orbit. The neutron shower from galactic cosmic rays causes more cloud formation, which in turn reflects more sunlight back into space, making the Earth colder. … In the second route, the lower magnetic field strength results in a lower temperature of the Sun’s chromosphere, which in turn produces less ultraviolet light. That decreases the production of lower stratospheric ozone, and that decrease causes a negative North Atlantic Oscillation (a fluctuation in sea-level atmospheric pressure), making the Northern Hemisphere colder. This second route makes winters longer and colder without necessarily reducing peak summer temperatures. [4] If solar magnetic activity really changes cloud cover, the incident radiance on the earth should vary with the sun's magnetic activity. That has been observed just as the solar theory predicts. [5] Solar activity is measured historically by the formation of beryllium 10, which accumulates in sediments to provide a history of solar activity. “The Modern Warm Period from 1900 to 2008 is associated with a large decline in Be10 in ice cores, indicating a sustained higher level of solar activity in the twentieth century. There is also very close correlation between ice-rafted stone debris in the North Atlantic and Be10 levels over the last 10,000 years—another demonstration that solar activity controls climate.” [6] The correlation continues through to the present day. Solar activity predicts the 17+ year halt in global warming as the cycle has reached a flat peak and is starting downward. The pause in global warming is illustrated in this graph: [7]: The AGW computer models include irradiance, which is essentially constant, but the models take no account at all of the solar magnetic effects that correlate tightly with climate. AGW theorists now admit that the CO2 models cannot be tweaked to explain the pause. They are now proposing a variety of new theories to patch the failed old theory. [8] One theory is that for some reason all the warming is going into the deep oceans. Another theory is that atmospheric aerosols (i.e., soot) is reducing the size of rain drops causing clouds to be whiter and reflect more energy. There are other theories. The problem is that if there is any uncalculated factor that completely wipes out CO2 effects, that admits CO2 does not dominate climate. If uncalculated factors can be as large or larger than the CO2 effect, that admits that previous warming might have been the result of unknown factors as well. The premise of the AGW theory was that because all the other factors affecting climate were known, CO2 must have caused the warming from 1983 to 1996. Historically, solar activity drives climate with CO2 rising after there is warmingAl Gore famously showed two graphs, one of temperature over time and one of CO2 over time. The shapes of the curves were similar, showing a high correlation. Mr. Gore never overlaid the graphs. Had he done so, it would have been apparent that CO2 levels were following the warming rather by hundreds of years rather than leading it. As the oceans warm, they can dissolve less CO2, which is then released into the atmosphere. The CO2 rise is in response to the solar magnetic effects that changed cloud cover to cause the basic climate change.Over long periods of earth's history, there is no relationship between CO2 and climate.[8] Consensus does not determine sciencePro has the burden of proving that human activity has dominated climate. My burden is only to show that the anthropogenic theory is unproved. A scientific theory is wrong if it fails to explain or predict, and anthropogenic theory has clearly failed. I'm not obligated to prove an alternative theory, but I nonetheless shown that solar magnetic activity explains and predicts climate much better than CO2 theory. Since solar magnetic activity has dominated climate, anthropogenic causes cannot be dominant. AGW theorists admit that factors not in their computer models have been so large as to completely cancel greenhouse gas effects. for the past 17+ years.Pro stresses that it is not just that a consensus exists, but that the consensus is based on data. (Actually, the only real data is a general increase in temperature which solar theory better explains, and the rest is computer models that did not predict the hiatus.) But every scientific consensus has been supported by data that scientists at the time thought conclusive. A wrong consensus means that the data was incorrect or that it was incorrectly interpreted. The once near-unanimous consensus that the earth was the center of the universe was based upon the indisputable observation that the sky appears to rotate around the earth. The theory was found wrong only by more careful observations starting with the inconsistent behavior of the paths of planets in the sky. In the 1960s, the scientific consensus favored the Steady State Theory over the Big Bang Theory. The Big Bang Theory predicted the presence of microwave background radiation, so when the background radiation was discovered, the consensus changed rapidly. Not long ago, the learned scientific consensus was that homosexuality was a form of mental illness. Psychologists thought they had the data to prove it, but they were wrong; it is genetic. Modern scientists continue to make errors reflected in wrong consensus. A very strong scientific consensus has until the past few years supported the theory that in the human diet, saturated fat causes high serum cholesterol levels which in turn causes heart disease. It turns out the original theory was based upon falsified data. The landmark peer that "proved" the theory deliberately excluded data that falsified the theory. A couple of other bogus papers supported the theory, including one in which cholesterol was injected into vegetarian rabbits, who then quite predictably died. Studies over the past fifty years that attempted to confirm the theory instead disproved it. [9, 10] The originator of the cholesterol theory believed it, and he did a great job of selling the theory so it quickly reached consensus.. Many papers giving the “wrong” results were not allowed to be published, or the authors declined to submit them for fear of ruining their reputation. Some scientists published after they retired so that career retribution could not be inflicted. I recite the cholesterol consensus error because it's very close to the way anthropogenic global warming theory has achieved consensus. Early enthusiastic advocates sold the theory as the only possible explanation of the rapid rise of temperatures from 1983 to 1996. According to that data, not only was CO2 the cause, but climate sensitivity much have been very large, perhaps five or even ten. Now Pro's claim is that it is at least 0.7. If it is that low, then global warming is not a crisis. it's hardly worth noting. The bogus 97% consensus comes from surveying only journals that refuse to publish dissent. The Climategate scandal showed how eager AGW are to suppress dissent."In a November 15, 2005, email Mann expresses his satisfaction that Geophysical Research Letters is now firmly under the control of the climate change alarmists but laments that other publications still publish research by skeptics: “The Geophysical Research Letters leak may have been plugged up now with new editorial leadership there, but these guys always have Climate Research and Energy and Environment, and will go there if necessary.” [9]Very few papers scientific papers say anything about global warming as whole. For example, there are about 200 papers that show that the Medieval Warm Period and similar climate change existed worldwide, and that refute the bogus Hockey Stick argument for AGW. But the papers would not be counted as being in opposition to AGW. Besides, they are in the wrong journals. Virtually all the papers on solar theory -- there are hundreds -- are in specialist journals, not the surveyed climate journals. ------------------------------------------Per the terms of of the debate, I'll put the reference list in the debate comments.

Global Warming is not significantly affected by human activity Now, in debunking the opponent’s case, we have to observe one thing; accordingly to the Industrial Revolution/Co2 release correlation graph, we can see that the Co2 release has gone outside the main tenants of the normal Co2 equilibrium, which accordingly is around (when effected by negative feedback) 200ppmv. However, we humans now have a ppmv-Co2 rate of 380ppmv, henceforth this may be an offspring, but very unlikely, of huge negative feedback, or it may be the beginning of huge positive feedback in the creation of a new Venus-like Equilibrium. The opponent mentions the 100,000 years Ice Age Cycle phenomenon; henceforth, we are heading towards another “Ice Age” in the opponent’s view. Firstly, the world’s orbit-tilt, which causes the earth’s temperature to change (as well as volcanoes), are not acting as strong as they were during the last Ice Age. This means that the current Interglacial might be extended by 10,000 years. Apart from this, the plethora of Greenhouse Release, from Co2 and other gasses, outweigh the cooling capacity of the world. If they weren’t, then the world would have been experiencing a period of cool-down, perhaps a mini-Ice Age, from the 1950s. However, as seen, this has not been the case. [1] Apart from this, the opponent’s graph seems to show that in each 100,000 year Ice Age cycles; there has been a natural release of Co2 that has caused a gradual change in temperature. However, scientists know about how this change of temperature came about already. Interglacial epochs were characterized by the balance of Co2 concentration in the air and the Co2 sink in the ocean. There have been occasional times of massive Co2 release rise from volcanic eruptions known as large igneous provinces. These large igneous provinces have been known to cause a sudden change in temperature; however, there are no large igneous provinces that are active. Apart from this, one must observe the fact that today’s volcano does not emit as much Co2 as humans. In fact, accordingly to the USGS, annually humans generate 130 times more Co2 gas than volcanoes. The opponent is implying that there are natural causes for Co2 and other greenhouse gas release in the world; however, there is a plethora of evidence that suggests the contrary. This data has already been presented. Apart from this, correlation is not causation; because the current Co2 rates in the atmosphere correlates with those of ancient times (which it does not, as already stated), does not mean that this rapid release of Co2 has not been caused by humans. The opponent must observe; there is a difference between gradual change and sudden change. Gradual change implies that the change is made clear gradually. Sudden change is built upon the common knowledge that this change is sudden and unexpected. If this were to have been gradual change, then we humans would have knew about this much later; however, that is not the case. The opponent seems to argue that this change is normal for the earth; however, we must see that before 1750, Co2 was at a rate of 20ppm in the atmosphere; however, this Co2 rate rose rapidly from 1750, after the industrialization of human capital output capabilities. Now it is at 379ppm, an 18 times increase from the pre-1750 rate. Fossil fuel usage has released 7.2 gigaton of Co2 in 2000-2005. (gigaton-1 billion metric tons). One cannot simply argue that humans do not play a massive role; we are messing with the earth’s ability to absorb Co2 via deforestation, as well as adding 42% more Co2 into the earth’s atmosphere within the last 300 years. Humans have, in a significant manner, effected the overall global temperature. Citations: [1] . http://www.skepticalscience.com...

Is Human Activity an addition to increased Global Warming/Climate Change Thank you for your quick response. Your position was human activity is an addition to increased Global Warming/ Climate Change. My position was that human activity is an addition to climate change just like other species. You can say human activity contributed more global warming than other species, but no more than the sun. So why aim the gun at us only? If we want to save humanity or other life on earth in the long run, we should not focus our effort in fighting over something insignificant as our demise is inevitable due to the sun. Maybe we should consider decreasing the sun activity to receive a greater impact. The statement " human activity is an addition to increased Global Warming/ Climate Change" is only partially true, and therefore is not the truth, and could be considered to be false if it is not the entire truth. With technological advancement, we might just be able to put on an extremely large sun glass to protect our earth from the sun's harmful activity. You may see human advancement or human activities to be harmful, but it could be the necessary ingredient to save the day.

Human activities are the main cause global warming. Okay, so I would like to agree with all of your definitions starting off, and we are going to keep the terms so we don't have definition clashes (like value clashes except more annoying…just kidding I love clashes of any kind that is why I debate) I would like to quickly define predicted: foretell on the basis of observation, experience, or scientific reason. (Merriam-webster) For my quick resolutional analysis, I will state: going by your definitions, mainly that of your global warming definition, all I have to prove is that human activities are the main cause of pollution, which according to your definition of global warming is the predicted cause of, and to show that the prediction is based off of observation, experience or scientific reason. 1st point: Humans are the main cause of Pollution. According to library.thinkquest.org, there are six different kinds of pollution: air, water, land, noise, radioactive, and thermal. a)air- air pollution is mostly caused by motor vehicle exhaust and industrial processes. Through motor vehicle exhaust, the combustion of the fuel creates oxides of lead, nitrogen, and sulpher. These oxides are more commonly known as ‘smog' and when they dissolve into water vapors they create acid rain. Industrial processes create big black smoke, (seen near many cities nowadays) that is nothing more than a gigantic creator of CFC's (clarification: chlorofluorocarbon) that rearrange the structure of the O otherwise known as the ozone layer gas. b) water-defined as being foreign matter that deteriorates the quality of water. The main causes are: petroleum based products, agriculture chemicals, and soil pollution. Quick run through, oil spills etc., pesticides that cover fruits and veggies that humans and animals eat, and finally our chemicals that seep through the ground and enter underground resevoirs. c)land- decomposition of solid waste, and the accumulation of non-biodegradable materials. Also the destruction of our environment falls into this category, such as the fact that every year we are losing 6 million hectares of land, loss of 24 billion tons of topsoil (the soil that lets us grow food), loss of 15 million acres of prime farm land to mismanagement and overuse, etc... the list goes on. d)noise-not a very popular pollution that people focuse on, but here we go: road traffic noise, air traffic, rail traffic, neighborhood noise, industrial noises, etc. while there are natural noises such as waves hitting the beach or even mating calls of monkeys, that are grossly overshadowed by the noise we cause. e)radioactive- the main causes are the disposal of nuclear waste, and nuclear weapons and nuclear powerplants. i think you get this point but just a quickfact, the half life of these radioactive substances have half lives of over 10,000 years. Right now the best america can do is bury these deep underground in some bunker in nevada. f)thermal- the most important type of pollution that is related to this debate. the two types that direct us the most, but are not thought about as much are the deforestation of shorelines and soil erosion. the first one, the deforestation of shorelines contributes greatly to the fact that the trees once holding the shoreline together are now being harvested for paper and etc. without these trees, not only is more soil going into the water, but also increases the amount of surface area of the water. the second type helps explains this more, soil erosion. muddy water that is created by the deforestation of shorelines, makes this water filled with sediment and other materials that have increased the light absorbtion into the water. Because the water now has much more light absorbtion, increasing the temperature of the water. This water heats up, and now we have melting polar ice caps. yes, the melting polar ice caps. Just as an example we have the Ward Hunt Ice shelf that has been in solid condition for the past 3,000 years. It started cracking in 2000 and now is currently in pieces. (NASA) When these break off, they start melting in the much warmer salt water and then raise the water level. And because there are less ice shelves, there is not as much sunlight being reflected back into space, rather more sunlight being absorbed. The cycle just continues over and over. 2) Global Warming Theory exists off of observation, experience and scientific reason. The people who are mostly pushing this theory is the IPCC (Intergovernment Panel on Climate Change) who is made up of over 350 scientific experts and government representatives, and their report was contributed and edited by over 2500 scientific expert reviewers, more than 800 contributing authors, and more than 450 lead authors (IPCC) all from over 130 countries. The specific summary for policy makers included 600 authors from over 40 different countries, more than 620 expert reviewers, and government reviewers and representatives from over 113 countries. (IPCC) I think this counts for observation and experience. For scientific reason, here is their reasoning: We are certain of the following: there is a greenhouse effect...; emissions resulting from human activities are substantially increasing the atmospheric concentrations of the greenhouse gases: CO2, methane, CFCs and nitrous oxide. These increases will enhance the greenhouse effect, resulting on average in an additional warming of the Earth's surface. The main greenhouse gas, water vapour, will increase in response to global warming and further enhance it. We calculate with confidence that: ...CO2 has been responsible for over half the enhanced greenhouse effect; long-lived gases would require immediate reductions in emissions from human activities of over 60% to stabilise their concentrations at today's levels... For my arguments: 1)Yes I agree that over a period of several hundred years the temperature will slowly rise, but to have such dramatic rise in the past few years is not the earth in a cycle, but rather outside influences, more specifically human influences. If we look to my information, supported by the UN and more than 130 countries, as well as hundred of climate experts, they all found the same thing, humans are affecting global warming whether we want to admit it or not. More than that, they have found that we are the cause of over 50% of it all. 2)For burning fossil fuels is only 18%, yes I agree with that too. But, we are not looking to ONLY fossil fuels contributing to greenhouse gases. Methane is not a fossil fuel (look to livestock raised by farmers..;)..) yet it contributes greatly to the global warming problem. If you look back to my first point and proof of pollution and greenhouse gases (specifically water vapor) we see that we do cause the majority. good luck KB

The significant bulk of scientific research says it is happening The biggest collection of specialist scientists in the world say that the worlds climate is changing as a result of human activity. The scientific community almost unanimously agrees that man-caused global warming is a severe threat, and the evidence is stacking.

Humans are responsible for global warming It's been said that humans are responsible for "Global Warming" due to our carbon emissions and high atmospheric pollution rate. While I agree that we are polluting the atmosphere at an extremely high rate, I disagree that, our carbon emissions are to blame. According to Science Magazine, measurements of ice core samples show that over the last four climactic cycles (past 240,000 years), periods of natural global warming preceded global increases in CO2. Also, A 2005 study published in Nature found that "high temperatures - similar to those observed in the twentieth century before 1990 - occurred around AD 1000 to 1100" in the Northern Hemisphere. Also, any human produced CO2 is re absorbed by the oceans, trees and plants, preventing the CO2 from gathering in the atmosphere. I look forward to debating you, and good luck!!

Human activities are the main cause global warming. wow Krebs, way to show up BUDDY. If we were in a real debate round I would have to insist that I take this match because of my opponents lack of second speech. Because of this, I have nothing to rebutt.

Anthropogenic Global Warming Denial I was expecting Pro to make an argument for Resolution B in his opening statement, since he bears the burden of proof. Since he has not done so, I will present a brief prima facie case against the Resolution. I disclaim that by doing so, I in no way assume the burden of proof with regard to the resolution; Pro bears the responsibility to refute my case and to present a case in favor of the resolution.For purposes of this debate, it is stipulated that global warming is taking place. The instant question is, are humans a significant contributing factor?A) Carbon dioxide has three isotopes: 12C, 13C and 14C. These account for, respectively, 99%, 1%, and 1 trillionth of the CO2 in the atmosphere (14C being radioactive).Plants prefer 12C over 13C. The 13C:12C ratio in plants is about 2% lower than in the atmosphere. Burning fossil fuels, which largely consist of ancient plants, thus results in a decrease in atmospheric 13C:12C ratio, which is exactly what we have been observing since the Industrial Revolution.[1]The only known source of carbon outgassing with such a low 13C:12C ratio is volcanic activity, and human activities release about 130 times the CO2 as volcanic activity every year.[2]B) The ratio of 14C:12C, as measured in tree ring data, steadily decreased from the Industrial Revolution until after World War II, during which the amount of 14C in the air was steady (after WW2, nuclear testing increased the 14C in the air). This is clear evidence that 12C increased during this period which coincided with industrialization.[3]By how much has it increased? From 1751 until 2006, humans have emitted an estimated 329,000,000,000 tons of CO2 into the atmosphere. That's 329 billion. Moreover, about half of those emissions come from the last three decades.[4]C) Apart from fossil fuel burning, common sense dictates another source of increased CO2: since before 1800, land clearance has resulted in dramatically fewer plants in the world, which in turn results in less carbon absorbsion, which means more CO2 in the atmosphere. This image (http://bit.ly...) shows the estimated anthropogenic carbon sources from both land clearance and fossil fuel burning since about 1750.In light of A, B and C, there is no plausible explanation for the sharp amount of CO2 increase in the atmosphere other than human activities. So, how do we know that CO2 is a significant cause of the observed global warming?D) Satellites have been observing the amount of Earth's heat escaping into space, particularly at the wavelengths at which CO2 absorbs heat. That amount has decreased.[1] Surface measurements observe heat at those same wavelengths spreading downward to the surface.[5]E) A CO2-caused greenhouse effect would have certain consequences: for instance, that the planet would be warming faster during the night than during the day, that the stratosphere and ionosphere would be cooling, and that the tropopause (the boundary between troposphere and stratosphere) would be rising. All of these effects are presently being observed.[6][7][8][9]Although this debate does allow a separate pages for sources, there is sufficient room in this statement to list my sources below:[1] IPCC, "Climate change 2007: The physical science basis. Contribution of working group I to the fourth assessment report of the intergovernmental panel on climate change," Solomon, S. et al., eds. (Cambridge University Press, 2007).[2] United States Geological Survey "Volcanic gases and their effects." Retrieved April 19, 2010 from USGS Web site: http://volcanoes.usgs.gov...[3] Ruddiman, W.F., Earth's Climate: Past and Future, 2nd. ed.. (W. H. Freeman & Co, 2008).[4] Boden, T.A., et al, "Global, regional, and national fossil-fuel co2 emissions." Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy (2009).[5] Wang, K. et al, "Global atmospheric downward longwave radiation over land surface under all-sky conditions from 1973 to 2008," Journal of Geophysical Research 114 (2009).[6] Alexander, L.V., et al, "Global observed changes in daily climate extremes of temperature and precipitationJ. Geophys. Res., 2006, 111, doi:10.1029/2005JD006290.[7] Jones, G.S, et al, "Causes of atmospheric temperature change 1960-2000: A combined attribution analysis," Geophysical Research Letters 30, 1228, 4 pp. (2003)[8] Santer, B.D., et al, "Contributions of Anthropogenic and Natural Forcing to Recent Tropopause Height Changes," Science 301 (2003), pp. 479-483.[9] Lastovicka, J., et al, "Global Change in the Upper Atmophere," Science 314 (2006), pp. 1253-1254.

Global Warming is Man-Made He is one of the best debaters on the site and is very knowledgeable on this subject. It is a pleasure to debate him. ==There exists a scientific consensus== Before I continue, I would like to note this argument in and of itself does not prove that global warming is caused by man. Actual evidence should be the driving force behind this debate. The reason I chose to put this in my argument is simple: the science is not clear because of consensus, but a consensus exists because the evidence is clear. This evidence will be discussed later. A study published in Science reviewed the ISI web of science in order to take a survey of relevant climate literature as to what the causes of climate change are. The study failed to find a single paper which was in opposition to the consensus position, that the main driver of climate change is anthropogenic. 75% of the papers supported the consensus position, whereas 25% had no position (they were focused on things other than forgings, like impacts or paleoclimate) [1]. The study also noted how many organizations have come out supporting the idea of anthropogenic climate change. The IPCC, the American Meteorological Society, American Geophysical Union, and the American Association for the Advancement of Science have all concluded that the evidence for AGW is overwhelming [2]. NASA furthers this argument, noting “most of the leading scientific organizations worldwide have issued public statements endorsing this position”. They also argue “[n]inety-seven percent of climate scientists agree that climate-warming trends over the past century are very likely due to human activities” [3]. A 196 page report representing 13 governmental agencies, and written by 28 authors from scientific institutions, has stated “[t]he global warming of the past 50 years is due primarily to human-induced increases in heat-trapping gases” [4]. ==Climate sensitivity== As Roy is well aware, this is the key point in all of climate science (we have discussed this before in a PM). For those who are unaware, climate sensitivity is defined as how much warming is produced by a doubling of CO2. Both skeptics and AGW supporters agree that the direct effect of doubling CO2 is one degree C, the debate is over feedbacks [5]. First, what is a feedback? Climate skeptic Roy Spencer explains it fairly simply. He describes a forcing as how much temperature change occurs. A feedback determines how large the change in temperatures will be. Feedbacks refer to how clouds and other warming/cooling mechanisms change in response to a forcing (i. e. CO2, TSI, CRs). He also explains positive and negative feedbacks. Take a car, for example. The temperature forcing would be the sun beating down on the car. Opening the window slowly would cool the car, over time, and be a negative feedback. On the other hand, if you were to close the window, the car would warm (due to an enhanced greenhouse effect), which would be a positive feedback [6]. So the question is whether or not the climate is dominated by negative or positive feedbacks. There is even the possibility of there being no feedbacks, as the positive and negatives could cancel each other out. Research by climate skeptics published in Climate Research has demonstrated that climate sensitivity, based on model means, is 1.9 degrees C. Using differing methods of empirical approaches, they conclude that climate sensitivity is 1 – 1.6 degrees C [7]. Although these estimates shy towards having no net-amplifier, the no-amplification scenario still supports a strong influence of man on climate. In fact, to put an answer numerically, about 50% of the warming would be caused by man if there was no net-feedback [8]. Assuming no amplifier, research has found that “the largest contribution to the 20th century warming comes from anthropogenic sources” [9]. They find that of the ~0.7 degree C temperature rise in the 20th century (some estimates slightly higher), about 0.4 degrees of that are due to anthropogenic forgings, or about 57% of the warming (personal calculation from these skeptical studies and personal correspondence with their authors). A significant body of research notes that climate sensitivity is likely much higher. A review of the evidence in 2008 finds that mean climate sensitivity is 3 degrees C, with a range of 2 – 4.5 degrees C. Based on multiple lines of evidence, we see *almost* every which way to measure climate sensitivity leads to approximately the same result: a doubling of CO2 will lead to 3 degrees C of temperature rise [10]. The following graphic from the study corroborates this: The gray is the range (2 – 4.5 degrees C), the line in the center is on 3 degrees C, and the circles in the lines are the ‘very likely’ ranges. Most of them rest on the 3 degree mark, with some under and some above. Therefore, we can conclude that from these lines of evidence, mean sensitivity is about 3 degrees C. Another study replicates the above conclusions. The upper limit for climate sensitivity is around 4 degrees C, and certainly below 6 degrees C. Using a Bayesian statistical approach, which is “the dominant [method] in the literature”, these findings support the notion of climate sensitivity as maximum 4 degrees C, a mean of 3 degrees C, and likely not lower than 3 degrees [11]. The following graph [12] again details the results of many different studies. The best estimates generally center around 2.5 – 3 degrees C. Some evidence published in 2012 claims sensitivity is on the low end of the spectrum, however, still note that “[h]umanity is . . . responsible for the most recent period of warming from 1976 to 2010” [13]. The fact is, climate sensitivity is high and the climate system is predominated by positive feedback mechanisms. Whether it be due to changes in clouds, increased water vapor, or long-term albedo changes. With a climate sensitivity of 1 (no positive or negative forcings), anthropogenic CO2 still causes up to 50% of the warming. With a climate sensitivity of 3 degrees C, humanity is the main driver of climate from about 1976 through present (see, e. g. , [13]). ==Paleoclimate== There is significant evidence from paleoclimate records that CO2 can have an effect on changes in the climate. Climate skeptic and paleoclimatologist Bob Carter emphasizes the importance of paleoclimate data. He compares climate to a piece of string. The current instrumental data (1850 – present) is a very short period of time, according to Carter. And when the ‘string’ is lengthened, we see a lot of climactic variability. Instead of looking at the recent past, we should look at the entire temperature record in order to get an accurate picture of the climate [14]. I will provide evidenc, contrary to what Carter believes, lengthening the string supports AGW theory. Over the Cenozoic Era, which began 66 million years ago, we see clear warming and cooling cycles caused by changes in CO2 concentrations. The sun increased slightly over that time period, whereas temperatures cooled. CO2, however, fell steadily through that time period. Plate tectonics was also accounted for. With natural forcings an unlikely cause, “CO2 was the dominant climate forcing in the Cenozoic” [15]. When you lengthen the ‘string’ over the course of the entire Phanerozoic (500 million years; begins at the Cambrian) there is still evidence of CO2 driving multiple climate changes. The GEOCARB study, published in 2001, is one of the definitive proxy records for CO2 concentrations within the last 500 million years. The study notes that “over the long term there is indeed a correlation between CO2 and paleotemperature” [16]. Evidence from the Vostok ice cores (specifically 240,000 before present), proves that CO2 has had an effect on temperatures. Although the initial forcing was orbital changes in the sun, CO2 “plays . . . a key role in amplifying the initial orbital forcing” and “the CO2 increase clearly precedes the Northern Hemi sphere deglaciation”. The study also notes that these forcings “are also at work for the present-day and future climate” [17]. There is also proof that it is warmer now than it has been since the MWP. In fact, it is warmer now than any year since 1400 AD [18]. Newer reconstructions continue to support this finding, and even extends the dataset. It finds that the Roman warm period (RWP) and the MWP as much cooler than today, and claims to have replicated previous ‘hockey stick’ studies [19]. The results are depicted below. Looking into the geologic past, we see strong evidence in favor of the idea that carbon dioxide can increase temperature. It logically follows that if humans continue to emit CO2, and other greenhouse gasses, that human emissions will increase temperatures. Conclusion: It is clear as to *why* a scientific consensus exists. There is overwhelming evidence that 1) climate sensitivity is likely high, 2) even if it wasn’t, anthropogenic forces still account for 50% or more of the warming (from CO2 alone, not counting methane and other greenhouse gases), and 3) that when you ‘lengthen’ the piece of string, there is still ample evidence ample evidence supporting the fact that CO2 can drive temperatures. The consensus itself does not prove AGW—but the evidence proves the consensus. CO2 is the main driver of recent temperature changes. Sources: . http://www.debate.org...

Humanity is the main cause of global warming. I do not dispute the existence and reality of Global Warming. I do assert, however, that it is impossible to quantify on a global scale, what part of global warming is attributable to Human activities as compared to natural change. Therefore, to state that humanity is the main cause of global warming is, at time present, impossible to prove. Geographers and Geologists consider the state of the Earth at time present to be in an ice age, albeit a late stage. This means that there have been periods in the history of the earth with less ice coverage, higher sea levels, and warmer mean global temperatures. As an example, a major component of the Glacial retreat we are witnessing today is attributable to natural rebound from the little ice age (approximately 1300 to 1850). Certainly human activity has amplified this rebound, but to what degree is indefinable. There are also many other potential amplifying factors, a few of which are listed on the Environmental Protection Agencies Website: . http://www3.epa.gov... Note, that even this reputable website is unable to quantify human contribution vs natural causes. I will also cite an article on the little ice-age for the benefit of my opponent: . http://www.britannica.com... I would also refer my opponent to the regional research of Glaciologist Dr. Johannes Koch regarding glacial retreat in Garibaldi Park (and other regional locations) which document the geological evidence of glacial retreat since the Little Ice Age glacial extant. The immense role of the Little Ice Age on climate is well established in this research. . http://kochj.brandonu.ca... or . http://kochj.brandonu.ca...

Humanity is the main cause of global warming. I never said that Mankind is the sole cause of global warming. I'm saying they are the main cause of global warming. According to the chart provided by Con in the previous argument, we are supposed going through a clod period. Then how come that 14 of the 15 hottest years are in the 21st century? This is shown in Wiki page of Global Warming. Therefore I respectfully say that the site might be wrong. Its true , there have been cold periods every year. But I think those are called winters. Another reason. Global Warming is primarily caused by emission of GHGs, or Greenhouse gases. The primary sources of GHGs are factories and automobiles . Which are human sources. The only major contributor from the natural side are trees which only emit CO2 during the night. Whereas human sources include, CO, CO2, nitrous oxide, methane and other synthetic chemicals emitted is vapour form by humans. And with the tree population declining, and not many volcanoes in the past 10 years, the GHG emission by nature are not that significant as mankind. http://environment.nationalgeographic.com... And contrary to common perception there has not been any cool period, the average surface temperature of the planet has been constantly increasing. The concentration of CO2 has been up about 20% from 650,000 years ago. Con has failed to rebut the argument of radioactive forcing which was in one of my sources. Just because its contribution cannot be quantified, doesn't mean it is not the major contributor. http://www3.epa.gov... In the above site, research has indicated that natural causes do not explain the recent climate changes . ( Ever since the Industrial Revolution). The site also gives the natural causes of climate change. 1)Variations in the sun's energy reaching Earth 2)Changes in the reflectivity of Earth"s atmosphere and surface 3)Changes in the greenhouse effect, which affects the amount of heat retained by Earth"s atmosphere 1)Its true that there have been changes in the Sun's energy reaching the Earth but none big enough to cause such a change in surface temperature ALONE. 2) The constant GHG emissions have damaged our ozone layer and are causing UV rays to enter the atmosphere which is also increase the temperature of the planet. Again . A human source. 3) The changes in the GreenHouse effect, is that we humans have been constantly increasing the amount of GHGs in the atmosphere in our quest for development and comfort. A human source. 4) There have been no volcanic eruptions, atleast not big enough for the atmosphere to change and for the aerosol count to become so high. Therefore one can conclude that a human source is now behind almost every natural cause that MAY have caused this spike in temperature. Therefore Humanity is the Main Cause of Global Warming.

Global Warming is caused by humans Good luck. I only have two points at the moment. So here they are: (1) Earth's mean surface temperature has increased about 1.2 degrees Fahrenheit. Scientist are more than 90% certain that human activities' such as burning fossil fuels and deforestation, is the primary cause of increases of the greenhouse effect. The Intergovernmental Panel on Climate Change (IPCC) indicates that the global surface temperature is likely to rise a lowest of 2 to 5.2 degrees Fahrenheit and a highest of 4.5 to 11.5 degrees during the 21st century. (2) According to NASA, human activities are changing the natural greenhouse. Over the last century the burning of fossil fuels like coal and oil have increased the concentration of atmospheric carbon dioxide (CO2) Sites: (1) en. wikipedia. org/wiki/Gobal_warming (2) climate. nasa. gov/causes/

Climate change is real and caused by humans First of all, let me apologize for not making it clear what I meant by "climate change." Global warming is actually an outdated term when it comes to climate change, and most scientists and climate activists prefer to now call it "climate change." Although overall temperatures are gradually getting higher, many people try to argue against the existence of climate change by referencing years when temperatures have been lower than normal. This winter has been a perfect example of this. Therefore, when I speak of "climate change" I am talking about the overall shift in global temperature, weather patterns, and other climate factors that we are already seeing today. Sorry for not making that clear. Because the evidence for actual climate change is unequivocal, with 97% of global scientists supporting it, I will not take most of this argument to show the evidence. The big thing we're debating is whether or not it is caused by humans. To start with evidence that climate change is happening, let me just list a few. First of all, ocean levels have been rising for the past century, with a total rise of about 6.7 inches (which may not sound like much, but globally has large implications, especially if it continues.) In addition, the rate of rising has doubled in the last decade compared with the last century, showing that temperatures are rising, and rising fast. Second, temperatures have been rising since 1880, and the most warming has happened since the 1970s, with the twenty hottest years having been since then. Third, the extent and thickness of Arctic sea ice has been declining rapidly over the past several decades. Fourth, since 1950, the number of record high temperatures has been increasing, while the number of record low temperatures has been decreasing. Fifth, since the Industrial Revolution, the acidity of the oceans has increased by about 30 percent! I will stop listing evidence here, so I can move on to why climate change is caused by humans, but I would end by reminding Con, as I said before, the 97 PERCENT OF ALL SCIENTISTS AGREE WITH THIS THEORY. Does that not mean anything? Now for some rebuttals against why Con said before. First of all to respond to what you said about how much CO2 humans release into the atmosphere compared to the amount released by the rest of the planet. It sounds like your saying that we have released 0.00022 percent of all CO2 ever released by the earth's mantle. This number doesn't have much relevance, and I will use a different one to respond. Humans currently release about 30 GT (giga-tons) of carbon each year, while the earth emits about 780 GT a year. While this may seem to show that humans aren't the problem, it actually shows that we are. Before we began emitting so much CO2, the system was in balance, with the earth and ocean absorbing the 780 GT that it emitted. This kept the CO2 level in the atmosphere between 180 and 280 parts per million for 800,000 years. With the added human carbon emission, the CO2 level is at 400 parts per million and still rising. For another rebuttal, I would respond to what you say about how significant climactic changes have happened throughout geologic time. This is true, but this does not make the climate change happening right now any less relevant. These changes in climate you speak of are called "Milankovitch cycles", which have to do with the periodic oscillation of the earth's tilt, the precession of the tilt, and changes in earth's elliptical orbit. During each of these warming cycles, CO2 and temperature levels have risen and fallen TOGETHER. Also, the whole sun theory you mention at the end of your argument was supported not by "a large body of scientific research", but by one man, Wei-Hock Soon, who got $1.2 million funding from fossil-fuel companies. I will end with this: climate change is an extremely important and urgent topic that needs to be addressed by the world. People like you (and I mean no offense) need to stop arguing, using the tiniest facts to try and disprove something that is so unanimously agreed upon by scientists worldwide. If you don't believe in science, then that is a whole different matter, but if you do, I cannot fathom why you don't understand this. If we don't have a habitable world to live and be healthy on, how can we solve all our other problems?

Anthropogenic climate change. I accept.

Many factors involved. When one is dealing with global warming one must take many factors into consideration. Thus human beings are not necessarily the ones affecting the planet. Firstly recorded history takes us back only 6 to 8 thousand years, while the Earth is approximately 4 billion years old. Thus man can not draw a definite conclusion on this issue based on the records kept in our short time here. Yes scientist have looked into both the polar and geological records, and it is true that the recent change in global temperatures have been dramatic. However if we were to look at the equation from a larger perspective, going back 600 thousand years we would find similar spikes in temperature. These spikes are due to the nature of the Earth's orbit around the sun, as the degree at which the Earth is orbiting the sun is in a state of continuous, albeit slow, change. As well scientist have recently confirmed that sunspot activity have reached a 1000 year high. Sunspots that send out thousands of cosmic rays that travel through space and constantly bombard Earth. Sunspots which may very well cause dramatic temperature rises on Earth, as suggest by scientist at the Institute for Astronomy in Zurich.

Mankind Is the Main Cause of Global Warming 1500-Year CyclesThe 1500-year cycles are not global. Most of the data that scientists have found on this has come from the northern hemisphere. However, in the southern hemisphere, the exact opposite trend happens. In other words, whenever the northern hemisphere is warming, the southern hemisphere is cooling, and vice versa. "Whereas Antarctic and Greenland climate records do exhibit approximate anti-phase behavior around 50% of the time, they are generally in phase during cooling. A phase lead of Southern Hemisphere climate of 1000-1600 years is statistically indistinguishable from a lag of 400-800 years, whether for Dansgaard-Oeschger [1500-year cycles], Heinrich, or longer-duration events. The "seesaw" or "Southern lead" appearance of the data arises from the fundamentally different characeristics of the climate series, most importantly the absence of rapid warming events in Antarctica comparable to those in Greenland". [1]However, in the current case, we see that both the northern and southern hemispheres are warming, meaning that it cannot be due to the 1500-year cycles. [2]Human Emissions of Carbon DioxideThe claim that CO2 levels were higher during certain ice ages is based off of old, faulty data. A recent study found that the levels during the Ordovician era (the era most climate skeptics focus on when making arguments like this) were eight times below pre-Industrial levels. This is indeed still a little high, but it's also important bearing in mind that the sun was dimmer then. During the Ordovician era, the sun was 4% dimmer. This meant that higher CO2 levels would have been necessary for Earth to have not been frozen over. This is based on established nuclear models of main sequence stars. Considering all of this, ". .. over the long term, there is indeed a correlation between CO2 and paleotemperature". [3][4][5]Apparent Mismatch Between CO2 and Temperature IncreasesIt is true that the vast majority of the warming happened over the 20th century. However, it is also true that the vast majority of the CO2 emitted into the atmosphere was emitted over the 20th century. See the graph below[6]: It is easy to see that only a small fraction of the emitted CO2 was emitted before 1900, and this correlates with the fact that only a small fraction of the temperature increases occurred before 1900. Amount of CO2 EmissionsAny CO2 emitted into the atmosphere would have an adverse effect on the climate. As I said in the last round, there was a study that said, using a Bayesian statistical approach, the climate sensitivity as maximum 4 degrees C, a mean of 3 degrees C, and likely value of not lower than 3 degrees. This means that the CO2 that humans emit thus has an effect of 3 degrees C per doubling of CO2. This can be shown by the fact that CO2 concentrations have increased from around 275 ppm to around 400 ppm. This is an increase of around 40%. This should manifest itself with a temperature increase of a little less than 1.5 degrees C. This is indeed around the amount of global warming we have seen so far. It should not be more than this. [7][8]If less CO2 had been added into the atmosphere, then the planet would have warmed less, but it still would have warmed. This would be true for any non-zero amount of CO2 emission. Climate ModelsThis point is irrelevant. The climate is much more complicated than just a correlation between CO2 and temperature (even though it still exists). Climate models have to be extraordinarily complicated, and even so, they might leave out very important climate forcings. Even if they didn't, there might still be glitches in the models that would make the model give an invalid result. The ability for climate models to accurately predict the climate is completely independent of the whether or not CO2 levels are related to temperature levelsIt is worth falsifying the notion, however, that there has been no warming since 2000. This idea is based on satellite measurements of atmospheric temperature. However, there are two problems with this. One, while the atmosphere accounts for only less than 3% of increased heat content, the oceans account for the vast majority, and they show no such trend. [9] The graph below shows this[10]: And two, there have been a lot of negative short term forcings over the last 20 years. Removing the short term trends of the extremely powerful El Nino in 1998, volcanic activity, and solar activity, the atmospheric temperature plot looks more smooth[11]: (You can faintly see what the plot looked like before the negative forcings were removed; the variability after 1998 makes any analysis before a statistical reanalysis suspect). Correlation Between CO2 Emissions and CO2 LevelsMany studies have shown that the "airborne fraction", or the fraction of human CO2 emissions that stay in the atmopshere, is around 43%. The fact that the CO2 levels flatlined during WWII is actually rather complicated. While military activity spiked, other industrial activity plummeted and millions of people died, decreasing the need for non-military CO2 emission even lower. In addition, CO2 levels are not known with the precision necessary to unravel this mystery before 1960, due to improper measuring techniques. There are simply too many factors too consider to make a sound conclusion here. As for the apparent 800-year lag in CO2 levels after temperature increases, this is indeed true. However, this is because there was no non-natural (i. e. human) forcing of CO2. Instead, another forcing initiates the warming trend, and CO2 amplifies it. "When the Earth comes out of an ice age, the warming is not initiated by CO2 but by changes in the Earth's orbit. The warming causes the oceans to release CO2. The CO2 amplifies the warming and mixes through the atmosphere, spreading warming throughout the planet. So CO2 causes warming and rising temperature causes CO2 rise. Overall, about 90% of the global warming occurs after the CO2 increase. "[12]Human Versus Natural CO2 EmissionNatural CO2 emissions are typically stable, meaning that there is rarely any long term climate change that results from natural emissions of CO2. However, humans have emitted a lot of CO2, above and beyond what is naturally emitted, and this unbalances the climate stability. "Although our output of 29 gigatons of CO2 is tiny compared to the 750 gigatons moving through the carbon cycle each year, it adds up because the land and ocean cannot absorb all of the extra CO2. About 40% of this additional CO2 is absorbed. The rest remains in the atmosphere. "[13]Solar ActivityThe most important of the natural climate forcings is indeed the sun. It is the source of the Earth's energy. This energy comes from the radiation emitted as a result of fusion reactions at the core of the sun. This radiation is known as the Total Solar Irradiance (TSI). Any change in the TSI causes energy imbalances on the Earth. This energy imbalance can be calculated using the formula below[14]: Delta means change, so Delta(F) means the change in energy (i. e. energy imbalance) and Delta(TSI) means the change in solar irradiance. The 0.7 factor comes from the fact that the Earth reflects about 30% of the solar radiation it receives, and the 1/4 factor comes from spherical geometry. Changes in temperature are proportional to the energy imbalance. This can be expressed in the formula below[14]: Lambda is the constant of proportionality, representing the climate sensitivity (discussed in my first argument) in this case. The only thing that's left is to actually determine the values. First, the change in TSI (in this case, between 1900 and 1950). ". .. we'll estimate the change in TSI at 0.5 to 2 W-m-2. " This corresponds to an energy imbalance of around 0.1-0.35 W-m-2. Next, the lambda factor. I explained in the last article that the statistically most probable value for the climate sensitivity was around 3 degrees C. But, there was a lot of variation. "Studies have given a possible range of values of 2 to 4.5°C warming for a doubling of CO2, which corresponds to a range of 0.54 to 1.2°C/(W-m-2) for λ. " This gives range of values from 0.05 to 0.4 degrees C, with a most probable value of 0.15 degrees C (corresponding to the statistically most likely climate sensitivity). In other words, solar activity from 1900 to 1950 raised the temperature of the Earth 0.15 degrees C. Looking at the effect of CO2 emissions over that same period, humans increased the concentration of CO2 in the atmosphere by about 20 parts per million, giving a range of values of 0.14-0.32 degrees C for the effect of that emission on the climate, with the most probable being 0.22 degrees C. [14][15]This corresponds to CO2 amounting for 60% of the warming from 1900-1950. After that, it gets higher. CO2 emissions rise exponentally, and changes in the TSI start getting less positive, and eventually become negative after 1975. "Over the past century, this increase in TSI is responsible for about 15-20% of global warming. But since TSI hasn't increased in at least the past 32 years (and more like 60 years, based on reconstructions), the Sun is not directly responsible for the warming over that period. " Solar activity cannot account for the warming after 1975, and even before that was a smaller factor than CO2. [14][15]This can be shown in the image below[16]: Therefore, we see CO2 correlates with recent temperature increases better than solar activity, especially after 1975. Long Term Forcings and MarsThe cycle of radiation is so long that it would not be having the sudden, enormous effect we've seen over the last 150 years. As for Mars, the studies concluded that it was a change in the surface dust, not solar activity, that caused the warming. Surface dust has a massive effect on Mars's climate. The supposed warming trend went from before the surface dust change to after it. Therefore, Mars did not warm because of solar activity. [17][18]SourcesSources in comments.

Humanity is the main cause of global warming. First of all I would like to apologise for themy forfeiture, as my internet connection was not available for a few days. I hope that voters disregard the forfeit. My opening statements. 1) Humanity IS the main cause of global warming.The IPCC Report of 2015 states: Its extremely likely that more than half of the observed increase in global average surface temperature from 1951 to 2010 wascaused by the anthropogenic increase in GHG concentrations and other anthropogenic forcings together. The best estimate of the human-induced contribution to warming is similar to the observed warming over this period . Anthro-pogenic forcings have likely made a substantial contribution to surface temperature increases since the mid-20th century over every continental region except Antarctica.. Anthropogenic influences have likely affected the global water cycle since 1960 and contributed to the retreat of glaciers since the 1960s and to the increased surface melting of the Greenland ice sheet since 1993. Anthropogenic influences have very likely contributed to Arctic sea-ice loss since 1979 and have very likely made a substantial contribution to increases in global upper ocean heat content (0""700 m) and to global mean sea level rise observed since the 1970s."One of the major contributions to global warming is caused by automobiles, a man made i.e. anthropogenic industry.Other include garbage disposal, factories, burning of leaves , bonfires etc. All of these are anthropogenic causes. 2) One could argue that global warming would take place with or without humanity , but that is not and would not have been the case. Global warming is not JUST the warming of the Earth , it is the EXCESSIVE warming of the Earth's atmosphere. 3) The following site also concludes that mankind is the main contributing factor of global warming. http://timeforchange.org... My Rebuttals 1) Con's source itself says that human activities have contributed substantially to climate change I.e. global warming. 2) I didn't know that global warming consisted of parts. Global warming, simply put is the heating up of the earth, which is mainly caused by greenhouse gases which are emitted by both anthropogenic and natural sources. But the amount is substantially more by man made sources. 3) Another reason given by Con's site is the sun's reflectivity , which can also be altered by human activities. 4) This debate is not whether this is the Little Ice Age or any other age. Its about mankind's impact on global warming. 5) Even if the role of Ice Age is as important as it is alleged, it cannot overtake the impact of civilization and development.

Anthropogenic global climate change. Round two argumentsOutline.I. Scientific consensus.II. Co2 is the main driver.III. The Co2 is from humans in lieu of natural.IV. Other supporting evidenceV. SourcesI. Scientific consensus.Claim: A scientific consensus exists for anthropogenic climate change existence. Warrant:"Multiple studies published in peer-reviewed scientific journals1 show that 97 percent or more of actively publishing climate scientists agree: Climate-warming trends over the past century are extremely likely due to human activities. In addition, most of the leading scientific organizations worldwide have issued public statements endorsing this position. The following is a partial list of these organizations, along with links to their published statements and a selection of related resources." [0]Impact: A scientific consensus is an agreement upon experts in the field. Think of one hundred heart surgeons agreeing upon a heart surgery technique. Heart surgeons would have more credibility than brain surgeons, dentists, and dermatologist. Even though all four are doctors, only the heart surgeons are most qualified on the subject of heart surgery. The same is true for climate scientists. A geologist, a physicist, and a biologist are all scientists. Yet, only climate scientists are the top notch for qualifications. These are the experts of experts in the field of climate science. There is nobody more qualified then this group of people. The fact that they came to a consensus based upon multiple lines of empirical evidence, used social calibration to determine what qualified as evidence, and social diversity, from many different parts of the world gives an enormous impact. The reason why social diversity is important is to avoid groupthink which can taint the consensus. "What Is Groupthink?Groupthink occurs when a group values harmony and coherance over accurate analysis and critical evaluation. It causes individual members of the group to unquestioningly follow the word of the leader and it strongly discourages any disagreement with the concensus. " [1]Here is the peer reviewed sources that confirm the scientific consensus. "J. Cook, et al, "Quantifying the consensus on anthropogenic global warming in the scientific literature," Environmental Research Letters Vol. 8 No. 2, (15 May 2013); DOI:10.1088/1748-9326/8/2/024024Quotation from page 3: "Among abstracts that expressed a position on AGW, 97.1% endorsed the scientific consensus. Among scientists who expressed a position on AGW in their abstract, 98.4% endorsed the consensus.”W. R. L. Anderegg, “Expert Credibility in Climate Change,” Proceedings of the National Academy of Sciences Vol. 107 No. 27, 12107-12109 (21 June 2010); DOI: 10.1073/pnas.1003187107.P. T. Doran & M. K. Zimmerman, "Examining the Scientific Consensus on Climate Change," Eos Transactions American Geophysical Union Vol. 90 Issue 3 (2009), 22; DOI: 10.1029/2009EO030002.N. Oreskes, “Beyond the Ivory Tower: The Scientific Consensus on Climate Change,” Science Vol. 306 no. 5702, p. 1686 (3 December 2004); DOI: 10.1126/science.1103618." [0]II. Co2 is the main driver.Claim: Co2 matter because the gas absorbs infrared radiation. Warrant:"Molecules of carbon dioxide (CO2) can absorb energy from infrared (IR) radiation. This animation shows a molecule of CO2 absorbing an incoming infrared photon (yellow arrows). The energy from the photon causes the CO2 molecule to vibrate. Shortly thereafter, the molecule gives up this extra energy by emitting another infrared photon. Once the extra energy has been removed by the emitted photon, the carbon dioxide stops vibrating." [2]Impact: Co2 absorbing infrared radiation plays a crucial part in the greenhouse gas rising of Earth's temperature. Claim: Co2 makes up 81% of the greenhouse gases.Warrant: [3] Pie graph should display here. Impact: This shows that Co2 is the main driver of climate change. III. The Co2 is from humans in lieu of natural. Claim: We know the Co2 is from humans due to human finger prints. Warrant: [4] Impact: These show that the Co2 is human caused as opposed to natural. IV. Other supporting evidenceThere is other supporting evidence, the over 400 ppm of Co2, sea level rise, global temperature rise which is now at 1.7 degree Fahrenheit, warming oceans, shrinking ice sheets, and many more. These all reinforce that anthropogenic climate change is happening. [5]V. Sources0. http://climate.nasa.gov...1. https://www.psychologytoday.com...2. https://scied.ucar.edu...3. https://www.epa.gov...4. https://skepticalscience.com...5. http://climate.nasa.gov...

Mankind Is the Main Cause of Global Warming "On the rebuttals, apologies. I misworded the debate structure. It should be "no rebuttals by pro." Just present your arguments affirming the resolution. Thanks."As said by Con, I will present my argumentsThe typical argument is like this [1] The Earth's atmosphere keeps the planet much warmer than it would be without an atmosphere. The main gases which contribute to this are carbon dioxide, methane and water vapor. Collectively these are called greenhouse gases. The ability of these gases to act as greenhouse gases can be shown in a laboratory. The quantity of these greenhouse gases in the atmosphere has increased sharply since the Industrial Revolution, and their concentration continues to do so. The concentration of these gases has increased as a consequence of human activity. The temperature of Earth's atmosphere has been increasing and continues to increase. The increase in global temperature correlates with the increases of greenhouse gases. Just about every scientist agrees with these 7 premises. Even some skeptics do too and I believe Con does (although I could be wrong). The following premise is the disputed one8. The increase in temperature has been caused by the increase in greenhouse gases from humans.We know the climate on Earth has changed before. We must understand that in order for a climate to rise naturally, A forcing must exist to force the climate to change. There's no known forcing that fits the fingerprint of the evidence we see, except one, anthropogenic greenhouse gases.We know that humans are producing 30 billion tons of Co2 a year in the atmosphere [3]. Let's see evidence that follows from this.I will paste 6 evidences from “10 Indicators of a Human Fingerprint on Climate Change” [2]1. When we measure the type of carbon accumulating in the atmosphere, we observe more of the type of carbon that comes from fossil fuels [4]2. This is corroborated by measurements of oxygen in the atmosphere. Oxygen levels are falling in line with the amount of carbon dioxide rising, just as you'd expect from fossil fuel burning which takes oxygen out of the air to create carbon dioxide [5]3. So we know humans are raising CO2 levels. What's the effect? Satellites measure less heat escaping out to space, at the particular wavelengths that CO2 absorbs heat, thus finding "direct experimental evidence for a significant increase in the Earth's greenhouse effect". [6]4. If an increased greenhouse effect is causing global warming, we should see certain patterns in the warming. For example, the planet should warm faster at night than during the day. This is indeed being observed [7]5. With the lower atmosphere (the troposphere) warming and the upper atmosphere (the stratosphere) cooling, another consequence is the boundary between the troposphere and stratosphere, otherwise known as the tropopause, should rise as a consequence of greenhouse warming. This has been observed [8]. This also contradicts the hypothesis that the earth is warming because of solar activity.6. ....A closer look at the downward radiation finds more heat returning at CO2 wavelengths, leading to the conclusion that "this experimental data should effectively end the argument by skeptics that no experimental evidence exists for the connection between greenhouse gas increases in the atmosphere and global warming." [9] [10]The resolution is affirmed[1] From http://rationalwiki.org... all references for the premises are within that[2] http://www.skepticalscience.com...[3] http://www.ldeo.columbia.edu...[4] http://www.esrl.noaa.gov...[5] Ibid[6] http://www.nature.com...[7] http://www.knmi.nl...[8] http://www.math.nyu.edu...[9] http://ams.confex.com...[10] http://www.agu.org...

Resolved: Climate change is, on balance, anthropogenic in origin C1) Climate sensitivity is likely high Climate sensitivity is the key argument to this debate. Everyone agrees that CO2 has some direct effect, at least 1 degree C per doubling of CO2 concentration. This is what former climate modeler turned skeptic David Evans argues. “[All] serious skeptical scientists have always agreed with the government climate scientists about the direct effect of CO2. The argument is entirely about the feedbacks.” [1] What are feedbacks? Feedbacks are important because they tell us how much warming we will have in the future. They amplify -- or dampen -- the warming effect of CO2. Changes in albedo, cloud cover, water vapor, and greenage can all affect warming. If sensitivity is 2-3 degrees C, CO2 can explain most of the warming since the late 70s. If it is lower it still causes a significant amount. My opponent needs to pretty much argue that the amplification effects are under one in order to win. Let us assume that climate sensitivity is low. Say, feedbacks are around zero (no positive or negative feedbacks); every doubling of CO2 leads to roughly 1.1 degrees C increase in temperature. Even this unrealistically low climate sensitivity does not harm the AGW hypothesis. Nir Al Shaviv, a skeptical physicist, wrote a paper assuming the feedback effect was 1.1 degrees. He calculated that CO2 actually caused slightly over half of the modern warming trend [2] (about 57%). The famous Lindzen and Choi (and Spencer) results are really the only ones which cast doubt on the fact that CO2 is responsible for the warming. But Nir Al Shaviv told me in an email, “[m]y best estimate is that the sensitivity is higher than Lindzen and Choi, actually closed to no net amplifier, with the 50% of the CO2 doubling, the Anthropogenic contribution is also around 50%.” [3] Essentially, he verified what I sent to him in an email with calculations I had done assuming the amplifier was flat. My data found that it caused about 49.5% of the warming, but I failed to take into account the logarithmic effect of CO2, which makes the effect over 50%. Even then, these assumptions are incorrect. Sensitivity is higher, and if it is, CO2 pretty much causes far more than 50% of the warming, but both estimates are enough to win me the debate. Research by Patrick Michaels, now a libertarian, CATO scholar found the amplifier to be 1.6 degrees C [4]. More than the 1.1 above. This puts the man made contribution to global warming above 50%, and certainly above 57%. This is not even including other gases which amplify the greenhouse effect. The burgeoning evidence suggests that the net amplifier is around 2-3 degrees C. Based on multiple lines of evidence, stemming from volcanic eruptions, instrumental records, paleoclimatology, and more, the mean sensitivity sits firmly at about 3 degrees C. The following picture demonstrates the evidence. As seen, the average never dips below 2 degrees C. The mean is 2 - 4.5 degrees C, all of which are enough for me to win the debate. 2 degrees C probably puts you around 70% of the warming is due to CO2, and 3 at nearly 100%, though I have not done the math (yet…). Some studies find fairly high sensitivity, around 4 degrees C. JD Annan, a leading climatologist, uses a Bayesian statistical technique, the predominant methodology in both the skeptic and realist literature. He found a mean sensitivity of 3 degrees C, with upper estimates at 4 degrees C, though still possible, but very unlikely below 3 degrees C [5]. The following graph [6], which I like because since I have used it pretty much everyone else has stolen it, shows the results from 3 leading studies. Although the results are uncertain, they are certain in that sensitivity is above 2 degrees C. A new paper, published in 2012, actually went against the consensus and found low sensitivity. Despite this, their results concluded that “[h]umanity is . . . responsible for the most recent period of warming from 1976 to 2010.” [7] Sensitivity is high. That means I win the debate. If it is low, I still win the debate because it caused 50% of more of the modern warm period. C2) Evidence from paleoclimatology I love paleoclimatology. I like geology and come from a family of geologists who are also oil entrepenueres (maybe why I still have skeptic leanings). And pretty solid evidence in the paleoclimatological record actually shows a strong CO2 effect. I am just going to c/p my debate with Roy. There is significant evidence from paleoclimate records that CO2 can have an effect on changes in the climate. Climate skeptic and paleoclimatologist Bob Carter emphasizes the importance of paleoclimate data. He compares climate to a piece of string. The current instrumental data (1850 – present) is a very short period of time, according to Carter. And when the ‘string’ is lengthened, we see a lot of climactic variability. Instead of looking at the recent past, we should look at the entire temperature record in order to get an accurate picture of the climate [8]. I will provide evidenc, contrary to what Carter believes, lengthening the string supports AGW theory. Over the Cenozoic Era, which began 66 million years ago, we see clear warming and cooling cycles caused by changes in CO2 concentrations. The sun increased slightly over that time period, whereas temperatures cooled. CO2, however, fell steadily through that time period. Plate tectonics was also accounted for. With natural forcings an unlikely cause, “CO2 was the dominant climate forcing in the Cenozoic” [9]. When you lengthen the ‘string’ over the course of the entire Phanerozoic (500 million years; begins at the Cambrian) there is still evidence of CO2 driving multiple climate changes. The GEOCARB study, published in 2001, is one of the definitive proxy records for CO2 concentrations within the last 500 million years. The study notes that “over the long term there is indeed a correlation between CO2 and paleotemperature” [10]. Evidence from the Vostok ice cores (specifically 240,000 before present), proves that CO2 has had an effect on temperatures. Although the initial forcing was orbital changes in the sun, CO2 “plays . . . a key role in amplifying the initial orbital forcing” and “the CO2 increase clearly precedes the Northern Hemisphere deglaciation”. The study also notes that these forcings “are also at work for the present-day and future climate” [11]. There is also proof that it is warmer now than it has been since the MWP. In fact, it is warmer now than any year since 1400 AD [12]. Newer reconstructions continue to support this finding, and even extends the dataset. It finds that the Roman warm period (RWP) and the MWP as much cooler than today, and claims to have replicated previous ‘hockey stick’ studies [19]. The results are depicted below. Looking into the geologic past, we see strong evidence in favor of the idea that carbon dioxide can increase temperature. It logically follows that if humans continue to emit CO2, and other greenhouse gasses, that human emissions will increase temperatures. C3) Consensus Before I continue, I would like to note this argument in and of itself does not prove that global warming is caused by man. Actual evidence should be the driving force behind this debate. The reason I chose to put this in my argument is simple: the science is not clear because of consensus, but a consensus exists because the evidence is clear. This evidence will be discussed later. A study published in Science reviewed the ISI web of science in order to take a survey of relevant climate literature as to what the causes of climate change are. The study failed to find a single paper which was in opposition to the consensus position, that the main driver of climate change is anthropogenic. 75% of the papers supported the consensus position, whereas 25% had no position (they were focused on things other than forgings, like impacts or paleoclimate) [14]. The study also noted how many organizations have come out supporting the idea of anthropogenic climate change. The IPCC, the American Meteorological Society, American Geophysical Union, and the American Association for the Advancement of Science have all concluded that the evidence for AGW is overwhelming [15]. NASA furthers this argument, noting “most of the leading scientific organizations worldwide have issued public statements endorsing this position”. They also argue “[n]inety-seven percent of climate scientists agree that climate-warming trends over the past century are very likely due to human activities” [16]. A 196 page report representing 13 governmental agencies, and written by 28 authors from scientific institutions, has stated “[t]he global warming of the past 50 years is due primarily to human-induced increases in heat-trapping gases” [17]. 1. https://mises.org... 2. http://www.phys.huji.ac.il... 3. Personal Correspondence. 4. http://www.int-res.com... 5. http://www.jamstec.go.jp... 6. http://www.skepticalscience.com... 7. http://www.scirp.org... 8. Bob Carter. Climate: The Counter Consensus (London: Stacey International, 2011). 9. http://www.columbia.edu... 10. http://earth.geology.yale.edu... 11. http://icebubbles.ucsd.edu... 12. http://www.atmosp.physics.utoronto.ca... 13. http://www.skepticalscience.com... 14. http://www.sciencemag.org... 15. Ibid. 16. http://climate.nasa.gov... 17. http://downloads.globalchange.gov...

Global Warming is caused by humans NASA states that, changes in the brightness of the Sun can influence the climate from decade to decade, but an increase in solar output falls short as an explanation for recent warming. (1) My argument: (1) Volcanoes release very small amounts of carbon dioxide compared to human emissions. (2) Not only have humans admitted carbon dioxide, but other greenhouse gases such as methane, nitrous oxide, and halocarbons, which are thickening the atmosphere. Thus causing heat to stay trapped close to the Earth's surface. Sites: (1) http://earthobservatory.nasa.gov... (2) http://www.globalchange.gov...

Mankind Is the Main Cause of Global Warming Numerous alternate causes to global warming prove that humans are not the primary source. Adopt a mindset of innocent until proven guilty, the affirmative must prove beyond correlation and doubt that human cause warming. The Pro must win that mankind is the "principal [and] leading" meaning that if I win that there is an alternative cause that is more responsible for warming than humans, or at least humans are not a major cause, then I win the debate. (First Pro speech)As the Con, I may contradict myself as my sole purpose is to disprove the Pro's statement. The Pro must remain consistent to prove their position.First, 1,500 year climate cycles. Fred Singer, an atmospheric and space physicist with a PhD from Princeton who founded the the Science and Environmental Policy Project (SEPP) and Nongovernmental International Panel on Climate Change (NIPCC), and Dennis Avery, a agricultural analyst who was awarded the National Intelligence Medal of Achievement, agree that there is substantial evidence around the world that climate cycles easily explain the warming we currently see. There is already a scientific consensus that cooling cycles (Ice Ages) exist, so it already not unreasonable to assume that warming cycles also exist. From 1300 to 1850, the Little Ice Age caused the earth to be about 2.5 degrees Celsius cooler than average. The Modern Warming portion of the cycle began in 1850, and "warming will continue for some time in the future, perhaps 200 years or more, regardless of human activity." Thus, today's warming can be explained by these climate cycles. These scientists gathered data from North America to Asia, and they use the ice caps in Greenland to further prove that by the way the ice formed, there must have been 1,500 year warming cycles. Sea sediment core in Ireland also shows the 1,500 year cycle. Fossilized pollen, boreholes, tree rings, and mountain tree lines all provide evidence to this theory because scientists can find how they were created or observe differing distances of tree rings to find the amount of warming that these objects underwent while being created. It's important to realize that completely dismissing 1,500 year cycles dismisses "human histories from the past 2,000 years...and a variety of physical evidence found by a huge body of serious researchers." (1) The Vostok ice sample that the rise and fall of CO2 correlate with natural cycles. Temperatures correlate with Ice Age minimus and maximus. There is a 420,000 thousand year cycle of carbon emissions. Given that humans release very little of the total carbon ouput, the correlation is between the carbon cycle and temperature cycle. (5)Secondly, human emissions of carbon dioxide are specifically not to blame. Patrick Moore, a former member of Greenpeace and an ecologist said the following while testifying in front of Congress: "There is no scientific proof that human emissions of carbon dioxide (CO2) are the dominant cause of the minor warming of the Earth's atmosphere over the past 100 years." In fact, carbon dioxide levels were 10x higher during the Ice Ages than they are now. This was also true 500 million years ago before evolution had created humans. Not only does this empiric disprove that humans are a major cause of increased carbon dioxide, but it also disproves that CO2 causing warming. Regardless of the theoretical examples the Pro provides, empirics trump. Third, the industrial revolution began in 1750, yet only from 1910 to 1940, there was an increase in .5 degrees Celsius of the global temperature. There was more than enough time for factories to produce enough carbon dioxide to have resulted in warming before those 200 years. This delay in increase prove that humans are not the main cause and is evidence of the climate cycles. (2) During this time, temperatures were much higher than today, but CO2 levels were lower. This places doubt in the significance of anthropogenic CO2 release. (7)Fourth, the climate rapidly changes to different stimuli. Anthony Lupo, assistant professor of atmospheric science at the University of Missouri at Columbia and an expert reviewer for the UN's Intergovernmental Panel on Climate Chang, discusses the fact that regional climates tend to experience much more change than globally. However, climates change rapidly, so if human emissions of CO2 really are responsible for warming, then 1) there should already be a much larger change in global temperature given the huge increase of CO2 emissions and 2) even when there were smaller amounts of CO2, this should have been enough to trigger an environmental change (3).Fifth, climate models fail. There was an increase in global temperature of 0.57C during the 30-year period from 1970 to 2000. Since then there has been no increase, perhaps a slight decrease, in average global temperature. This clearly disproves the numerous computer models that the Pro cites as CO2 had increased after 2000 (2). Many believe that there will be an increase of anywhere from 2-11 degrees Fahrenheit due to info from computer models. Misinterpretation of results and models lacking the complexities of the fundamental global processes mean that these cannot be trusted. Consistently, politicians like Al Gore have predicted that the world would have literally ended by now. Prefer direct facts and empirical examples rather than theoretical results of greenhouse gases. Thus, do not automatically trust that greenhouse gases cause warming without direct evidence from changes in temperature â€" the facts don't support this conclusion. (3) Though the Earth is warming, it's cooler than expected. There should have already been a two degree Celsius increase 100,000 years ago. (5) [Insert pie graph from this source]Sixth, fossil fuels do not cause an increase in CO2 levels according to the most accurate NASA data. From 1940 to 1950, CO2 levels flatlined. The only change was roughly .8 ppm downwards. World War II caused a massive increase in fossil fuel levels, yet this did not change CO2 levels. Prefer empirics. (4) Also, the Vostok ice core sample proves. CO2 increases did not increase temperature for 800 years. This sample also explains why a fall in temperature and a fall in CO2 correlate — cold water can hold more CO2 than warm water. Even more, temperature falls around 800-1,000 years before CO2 levels rise or fall giving water time to absorb the CO2. (5)Seventh, even if humans do increase CO2 levels, they're only responsible for a 3% increase. Even that released CO2 is not all directly released into the atmosphere given that the oceans absorb so much of it. Limestone, chalk, and other rocks have 100x as much CO2 as the atmosphere. This 3% is responsible for .27% of the greenhouse effect. "If we were to cease all transport and industry right now, it is very unrealistic to assume that it would have any impact on global warming." (5) Eighth, solar radiation is the single largest cause of warming. NASA repeatedly releases articles explaining the importance of the sun and sun cycles on the Earth. The near infrared and visible light waves are absorbed by the lower atmosphere, the oceans, and the land. Thus, these areas heat resulting in a higher global average temperature. Even more, absorption of UV rays heats the stratosphere. There's a general scientific consensus that this increases temperatures in the troposphere. Additionally, sun spots serve to reduce or increase warming. These can sway warming either way considering that these are 11 year cycles. This can explain why times of higher CO2 did not increase temperature. Scientists believe that the sun is responsible for at least half of all the climate change seen in the past 110 years. Even the IPCC, an organization devoted to creating response to globa warming, agrees. (6)The 100,000 year cycle of radiation resulting from the elliptical orbit of the Earth is at a peak and will be for the next several thousand years. This radiation is consistent with spikes in CO2 methane. The melting of ice caps has happened with each of these cycles. The huge volume of these gases is too high to be anthropogenic but is consistent with previous cycles. Mars is also increasing in temperature due to the recent increase in solar radiation. Dr. H. Abdussamatov, head of the St. Petersburg Pulkova Astronomical Observatory, believes that the Earth has hit a temperature ceiling and will enter a cooling period despite fossil fuel use. This explanation accounts for the lack of increased greenhouse gas emissions since 1988. (7) [Insert Figure III]ConclusionSolar radiation, solar cycles, and multiple terrestrial temperature cycles are greater and more probable causes of warming. Humans produce very little emissions given the oceans' absorption and solar radiation cycles. The Earth has consistently changed temperatures before humans populated the planet. Even more, multiple empirics and evidence from around the world disprove the importance of humans on warming. 3% is a ridiculously small number when compared to multiple other emittors. CO2 levels were higher in the Ice Age when the Earth was substantially cooler. By placing some amount of doubt in the significance of mankind's importance on warming while promoting several other causes, humans are at least not the main factor of warming.(1) http://www.ncpa.org...(2) http://www.dailymail.co.uk...(3) http://www.napsnet.com...(4)http://www.americanthinker.com...(5) http://www.collective-evolution.com...(6) http://earthobservatory.nasa.gov...(7) http://www.americanthinker.com...**I'm going to advertise my surveillance debate here: comment on that page if interested! :)

Man-Made Global Warming Isn't Real I will begin with a few statistics and quotes from experts showing, unequivocally, that global warming has occurred. I will then move on to show that this effect is largely a result of human actions, technology, and the like. Next, I will provide quotes and sources specifically stating that the current level(s) of global warming could not be results of natural causes. Finally, I will address some of the arguments Pro is likely to make. I will point out that, at least in the past, he/she references sites such as "Right Wing News" and "Breitbart", sources known to be some of the most biased that exist. On the other hand, the sources I reference are scholarly, scientific, and largely non-partisan. As the BoP is on Pro and he/she stated "man-made global warming isn't real", he/she will have to prove beyond a reasonable doubt (and refute all counter-claims on this topic) that none of the global warming that has occurred has resulted from human action. If even some of it has resulted from human action, it would, by definition, be "real".Global Warming Occurring- "Scientific evidence for warming of the climate system is unequivocal." - Intergovernmental Panel on Climate Change- The planet's average surface temperature has risen about 1.62 degrees Fahrenheit (0.9 degrees Celsius) since the late 19th century, a change driven largely by increased carbon dioxide and other human-made emissions into the atmosphere. Most of the warming occurred in the past 35 years, with the five warmest years on record taking place since 2010.- The Greenland and Antarctic ice sheets have decreased in mass. Data from NASA's Gravity Recovery and Climate Experiment show Greenland lost and average of 281 billion tons of ice per year between 1993 and 2016, while Antarctica lost about 119 billion tons during the same time period. The rate of Antarctica ice mass loss has tripled in the last decade.- Glaciers are retreating almost everywhere around the world — including in the Alps, Himalayas, Andes, Rockies, Alaska and Africa.- Satellite observations reveal that the amount of spring snow cover in the Northern Hemisphere has decreased over the past five decades and that the snow is melting earlier.- Global sea level rose about 8 inches in the last century. The rate in the last two decades, however, is nearly double that of the last century.- The number of record high temperature events in the United States has been increasing, while the number of record low temperature events has been decreasing, since 1950.- The Greenland and Antarctic ice sheets have decreased in mass. Data from NASA's Gravity Recovery and Climate Experiment show Greenland lost and average of 281 billion tons of ice per year between 1993 and 2016, while Antarctica lost about 119 billion tons during the same time period. The rate of Antarctica ice mass loss has tripled in the last decade.- Each of the last three decades has been successively warmer at the Earth’s surface than any preceding decade since 1850- "The danger is that global warming may become self-sustaining, if it has not done so already. The melting of the Arctic and Antarctic ice caps reduces the fraction of solar energy reflected back into space, and so increases the temperature further. Climate change may kill off the Amazon and other rain forests, and so eliminate once one of the main ways in which carbon dioxide is removed from the atmosphere. The rise in sea temperature may trigger the release of large quantities of carbon dioxide, trapped as hydrides on the ocean floor. Both these phenomena would increase the greenhouse effect, and so global warming further. We have to reverse global warming urgently, if we still can." - Stephen Hawking- Evidence from ocean sediments, ice cores, tree rings, sedimentary rocks and coral reefs show that the current warming is occurring 10 times faster than it did in the past when Earth emerged from the ice ages, at a rate unprecedented in the last 1,300 years.Sources:https://climate.nasa.gov... https://www.ncdc.noaa.gov... http://www.cru.uea.ac.uk... http://data.giss.nasa.gov... Levitus, et al, "Global ocean heat content 1955–2008 in light of recently revealed instrumentation problems," Geophys. Res. Lett. 36, L07608 (2009).http://nsidc.org...https://www.jpl.nasa.gov...http://blogs.ei.columbia.edu...IPCC Climate Change 2013: The Physical Science BasisHumans Are (at least partially) To Blame- "It is 'extremely likely that more than half of the observed increase in global average surface temperature' from 1951 to 2010 was caused by human activity. By 'extremely likely', it meant that there was between a 95% and 100% probability that more than half of modern warming was due to humans. - Intergovernmental Panel on Climate Change’s (IPCC) fifth assessment report.- "Between 93% to 123% of observed 1951-2010 warming was due to human activities." - US Fourth National Climate Assessment- "Scientists Agree: Global Warming is Happening and Humans are the Primary Cause" - UCSUSA- "Human influence on the climate system is clear, and recent anthropogenic emissions of green-house gases are the highest in history. […] Warming of the climate system is unequivocal, and since the 1950s, many of the observed changes are unprecedented over decades to millennia." - IPCC AR5- "Of all the radiative forcings analysed, only increases in greenhouse gas emissions produce the magnitude of warming experienced over the past 150 years." - Berkeley Earth- "Today, CO2 levels are 40 percent higher than they were before the Industrial Revolution began; they have risen from 280 parts per million in the 18th century to over 400 ppm in 2015 and are on track to reach 410 ppm this spring. In addition, there is much more methane (a greenhouse gas 84 times more potent than CO2 in the short term) in the atmosphere than at any time in the past 800,000 years—two and a half times as much as before the Industrial Revolution. While some methane is emitted naturally from wetlands, sediments, volcanoes and wildfires, the majority of methane emissions come from oil and gas production, livestock farming and landfills." - Earth Institute, Columbia University- "Today, almost 100 percent [plus or minus 20 percent] of the unusual warmth that we’ve experienced in the last decade is due to greenhouse gas emissions,” - Peter de Menocal, dean of science at Columbia University and founding director of Columbia’s Center for Climate and Life Note: Some of these conclusions have led to some confusion as to how more than 100% of observed warming could be attributable to human activity. A human contribution of greater than 100% is possible because natural climate change associated with volcanoes and solar activity would most likely have resulted in a slight cooling over the past 50 years, offsetting some of the warming associated with human activities.Current Levels of Global Warming Not Natural- "If the sun were brighter, we would see warming all the way up through the atmosphere from the surface to the stratosphere to the mesosphere. We don’t see this. We see instead warming at the surface, cooling in the stratosphere, cooling in the mesosphere. And that’s a signature of greenhouse gas forcing, it’s not a signature of solar forcing. So we know it’s not solar.” - Gavin Schmidt, director of National Aeronautics and Space Administration’s Goddard Institute for Space Studies- "Volcanoes have a short-term cooling effect on the climate due to their injection of sulphate aerosols high into the stratosphere, where they can remain aloft for a few years, reflecting incoming sunlight back into space." - Zeke Hausfather- "Finally, solar activity is measured by satellites over the past few decades and estimated based on sunspot counts in the more distant past. The amount of energy reaching the Earth from the sun fluctuates modestly on a cycle of around 11 years. There has been a slight increase in overall solar activity since the 1850s, but the amount of additional solar energy reaching the Earth is small compared to other radiative forcings examined. Over the past 50 years, solar energy reaching the Earth has actually declined slightly, while temperatures have increased dramatically." - Carbon Brief- “We have independent evidence that says when you put in greenhouse gases, you get the changes that we see. If you don’t put in greenhouse gases, you don’t. And if you put in all the other things people think about—the changes in the earth’s orbit, the ocean circulation changes, El Niño, land use changes, air pollution, smog, ozone depletion—all of those things, none of them actually produce the changes that we see in multiple data sets across multiple areas of the system, all of which have been independently replicated.” - Gavin Schmidt, director of National Aeronautics and Space Administration’s Goddard Institute for Space Studies Potential Pro ArgumentBased on Pro's past debates on this subject, I know he/she is likely to make following arguments:"https://goo.gl...;Sorry, you were saying..." Many people debate the validity of this statistic/image, but we can put that aside. Global warming is about the long-term trend, not a single year-over-year increase in the size of a particular ice sheet. So, even if this is accurate, it is in no way sufficient in disproving the litany of sources cited above stating the long-term trend. Here is a Forbes article directly speaking to statistics of this nature: https://goo.gl...As stated above, Pro's other arguments often rest on sources such as "Right Wing News" and "Breitbart", a few of the least reliable, least scientific, least objective sources in the world. I would point voters to the much more reputable, scientific, and unbiased sources I have used in my arguments.

Global Warming Exists I am eager to debate such an experienced member of this site. For my argument I would first off like to define a few terms as it is likely that they will be used several times by both debaters. Global warming: a gradual increase in the overall temperature of the earth's atmosphere. Greenhouse effect: the trapping of the sun's warmth in a planet's lower atmosphere. Carbon Dioxide (CO2): a colorless, odorless gas produced by burning carbon and organic compounds and by respiration. Fossil Fuels: a natural fuel such as coal or gas, formed in the geological past from the remains of living organisms. With the definitions aside, let the debating begin! How does the greenhouse effect work? Before I begin defending the premise defined in the first round, I would like to clarify how the process called the greenhouse effect works. This is essential to the topic of global warming, as the greenhouse effect is the process which warms the planet, especially during the nigh time. When sunlight reaches the earths atmosphere it changes into thermal radiation. Most of this thermal radiation is reflected off back into space due to the earth's atmosphere, however some manages to enter the planet. Once it reaches the atmosphere, it comes down to the surface, still as light, and is converted into energy through the process of photosynthesis. Eventually this energy is transferred from the plant to a primary or secondary consumer when the plant/producer is eaten by the consumer. Due to a concept called the 10% rule, almost all of the energy (90%) is lost during the transfer from producer to consumer and is radiated back into the atmosphere as heat [1]. Some of this heat manages to leave the atmosphere and goes off to space where it becomes essentially useless. A small percent of the heat, however, is trapped by the greenhouse gases (such as CO2, CH4, N2O, etc) and is kept in the atmosphere [2]. This is important because during the nigh time when the sun is not providing heat, the heat preserved by the greenhouse gases keep the planets surface warm [3]. This generally should be considered a good thing, however in this case there can be to much of a good thing. Due to the fact that there is now an abundance of greenhouse gases in the atmosphere, especially carbon dioxide, too much heat is being trapped in the atmosphere and as a result global temperatures have risen. I will attempt to prove that the reason for this abundance of greenhouse gases and as a result increased global temperatures is a result of human actions, and it is not a "natural" occurrence. Graph A shows the basic process of the greenhouse effect. Graph A: Argument structureMy argument will follow this basic format: P1) The increase of carbon dioxide in the atmosphere is a result of human actions. P2) Carbon dioxide in the atmosphere causes an increase in global temperatures. P3) Therefore human beings are responsible for global warming. P1) The increase of carbon dioxide in the atmosphere is a result of human actions. This is not a very difficult subject to defend and consequently it is not a very controversial subject, therefore I will be brief. Since the industrial revolution in the mid 1800's more and more carbon dioxide has been released into the atmosphere. Graph B shows the rapid increase in carbon emmisions starting in 1850. Graph B: The reason for this is obvious, due to rapid increasing of industry and technology, burning of fossil fuels has become more and more frequent. Due to the fact that the burning of fossil fuels emits carbon dioxide into the atmosphere, it is also obvious that the increased amount of carbon dioxide in the atmosphere is a result of human activity. P2) Carbon dioxide in the atmosphere causes an increase in global temperatures. This is a much more controversial subject, and therefore I will spend the majority of my argument in this section. Given that the greenhouse effect states that greenhouse gases trap heat, and re radiate it in all directions, as shown in Graph A, it would be easy to make the assumption that if there is more carbon dioxide in the atmosphere there would be less long wave radiation (the type of heat that CO2 absorbs) being emitted into space and more infrared radiation being emitted back to the earth. This, as a result, would heat up the world and cause global warming. To prove this hypothesis, NASA launched the IRIS satellite in 1970 to record the amount of long wave radiation being emitted into space over a 26 year period [4]. What they found supported the hypothesis that less long wave radiation was being emitted into space and as result their was more infrared being contained in the earth. Graph C displays the results of the experiment. Graph C: This graph is an infrared spectrum and it shows the frequencies of infrared light (800 to 1600 cm-1). The graph has multiple greenhouse gases (such as CO2 and CH4) and based on their position on the graph, it determines the frequency of infrared light that they absorb. For example CO2 is at the far end of the spectrum because it absorbs lower frequency light than CH4 (methane), which is at the far end of the spectrum. The graph shows the difference of the amount of infrared radiation that is being absorbed by the various greenhouse gases between 1970 and 1996. Due to the fact that there is a greater variation in both CO2 and CH4 it shows that there is more radiation being absorbed by those two gases. In simpler terms, this shows that there is more heat being trapped by carbon dioxide and methane then there used to in the past, and therefore as a result global warming is a result of the carbon dioxide and methane in the atmosphere. If these gases are the cause of global warming than it can also be determined that human beings are the cause of global warming because they are the ones that are emitting the CO2 and CH4 into the atmosphere. Moving on to the next graph, Graph D is representing the amount of infrared radiation at the earth's surface. Graph D: This graph is somewhat less complex than Graph C (thankfully). What it is representing is once again the infrared radiation spectrum (600-1800 cm-1) and the greenhouse gases that trap the radiation at certain spectrums. CO2 is found and approximately 800 cm-1 and consequently there is a much higher amount of infrared radiation at 800 cm-1 at the earths surface than there is of any other wave frequency. What this means is that carbon dioxide is responsible for the majority of the heat being contained in the earth. By extension, this means that carbon dioxide is causing global warming and that it is once again human beings fault due to the fact that we are the ones emitting the CO2 into the atmosphere. Now moving on to the final graph. Graph E is showing both the amount of carbon dioxide in the atmosphere and also the global temperatures. Graph E: What Graph E is conveying is that there is a huge amount of carbon dioxide in the atmosphere currently, much higher than there has ever been in the past. Now there are three important things to note in this graph. One is that throughout the course of history, whenever global temperatures increased, the carbon dioxide levels in the atmosphere had increased as well. This allows us to reach the conclusion that the more carbon dioxide in the atmosphere, the higher temperatures will be. The second thing to note is that in none of the historical situations did global temperatures increase at the exact same time that the carbon dioxide levels. In every situation the temperatures took several years to rise following an increase in carbon dioxide levels. This is important because it shows global warming skeptics, like my opponent, that global temperatures will not increase right away. This is why temperatures have not increased so rapidly yet, however given the trend of this graph they are certain to increase in the near future. The final thing to note is the huge amount of carbon dioxide in the atmosphere today. In no situation in history has their been such a high amount of carbon dioxide in the atmosphere, and the only explanation for why this is is human activity. Global warming skeptics claim that we cannot know that it is human being fault for global warming, however this chart shows the contrary. P3) Therefore humans are responsible for global warmingI have proved that carbon dioxide is the primary reason for why their has been increases in global temperatures as of late. This negates skeptics major arguments about why global warming is not human beings fault because it is clear that carbon dioxide emittions are due to human beings, and therefore it can be concluded that human beings are the cause of global warming. Sources[1] . http://en.wikipedia.org...[2] . http://www.epa.gov...[3] . http://hyperphysics.phy-astr.gsu.edu...[4] . http://www.skepticalscience.com...

CO2 emissions are directly responsible for climate change. The Macquarie Dictionary defines the term "climate change" as- a significant change in the usual climatic conditions especially that thought to be caused by global warming. This 'climate change' can be caused by natural or human induced impacts. The global average temperature has risen by nearly a degree in the past 50 years. Scientists around the world have been recording temperature increases, raised ocean levels and melting of ice caps. All this is evidence that the earth is experiencing a "climate change". Many people believe that this change is primarily due to the fact that our CO2 emissions have created more greenhouse gases. They believe that there is a relationship between the rise in temperatures and the rise in CO2 emissions. Data shows an "association" between temperature levels and CO2 emissions but does not necessarily prove that increased CO2 levels are the most significant aspect of today"s climate change. For something complex like the weather system, many scientists are needed to unravel the story behind climate change. While most scientists believe climate change occurs, not all agree on the extent and relevance of human activity as an influence on climate change. While major international climate agencies all emphasise the critical role of CO2 emissions in climate change, others are not so sure. For example, some scientists have conducted research that suggests that temperatures were higher than they are today, during the Roman and Medieval periods. These ancient civilisations would not have emitted CO2 emissions as we do today, so why did their temperatures rise? Temperatures have risen and fallen for a long time. The National Centre for Atmospheric Research (NCAR) states that climate change over the longer term is mainly due to the amount of sun energy hitting the Earth. Slight changes in the Earth"s orbit and changes in sun ray intensity, can alter the temperatures here on Earth. Even so, most scientists still emphasise the role of CO2 emissions in unprecedented, rapid global warming. The frank fact is that climate change cannot be stopped. It is completely natural.

Anthropogenic global warming is a threat Thanks for accepting. I did want arguments against GW to be posted in R1, but that's OK.BOP is shared.Here is the first 5 of "10 Indicators of a Human Fingerprint on Climate Change"[1] 1.Humans are currently emitting around 30 billion tonnes of CO2 into the atmosphere every year[2]. Of course, it could be coincidence that CO2 levels are rising so sharply at the same time so let's look at more evidence that we're responsible for the rise in CO2 levels. 2.When we measure the type of carbon accumulating in the atmosphere, we observe more of the type of carbon that comes from fossil fuels [3]. 3.This is corroborated by measurements of oxygen in the atmosphere. Oxygen levels are falling in line with the amount of carbon dioxide rising, just as you'd expect from fossil fuel burning which takes oxygen out of the air to create carbon dioxide [4]. 4.Further independent evidence that humans are raising CO2 levels comes from measurements of carbon found in coral records going back several centuries. These find a recent sharp rise in the type of carbon that comes from fossil fuels [5]. 5.So we know humans are raising CO2 levels. What's the effect? Satellites measure less heat escaping out to space, at the particular wavelengths that CO2 absorbs heat, thus finding "direct experimental evidence for a significant increase in the Earth's greenhouse effect".[6][7][1]http://www.skepticalscience.com...[2]http://cdiac.ornl.gov...[3]http://www.esrl.noaa.gov...[4]Ibid[5]http://www.sciencemag.org...[6]http://www.nature.com...[7]https://docs.google.com...

Many scientists think it does Anthropogenic effects on climate change are accepted by more than 99% of climate scientists. The longest, high resolution datasets in the world are land and sea surface temperature, collected since the 1860s, the errors of which have now been statistically corrected (Folland and Parker, 1995). Since the advent of climate modeling since the early 1990s, technology has improved so rapidly that scientists are now able to isolate the different forcings of climate change, and have shown unequivocally that natural variability, sun spots and volcanic activity are not able to explain the rise in global temperature, and that anthropogenic emissions of CO2 (which have been monitored in Hawaii since 1957) is the only plausible explanation for the additional, catastrophic rise in temperature.

Climate change I will present my position, and then I will state the things upon me and Con agree, then I will react to the arguments brought up by Con. My position I have stated that humans "drive" global warming in a significant degree. Significant is the key word here. Nobody is so naive to consider that global climate is driven only or even mostly by humans. That would be an absurd position and a probatio diabolica for Pro taking into account things like solar activity, ocean currents or vulcanic activity. I have chosen the more sane position that human activity is an important or significant factor of global warming. By this I understand that what we do with regard to greenhouse gases has consequences on the climate and ultimately on us. Consensus I agree with Con that this is a broad topic. However even from the second round there are things upon we have already agreed effectively narrowing the topic. The first agreed fact is that the climate is warming. This is an smart choice from Con, as it would have been more difficult to argue that the climate is not warming. Also, Con admits that humans have a marginal effect. I say that this effect is important. We also agree that we are talking only about greenhouse gases even if this reduces the examples that Pro can bring up. In addition I want to point out the contradiction between the second paragraph and the last paragraph of Con. In the first paragraph he admits that there is global warming and in the last paragraph he talks about cO2 increase not explaining "stable" recent temperatures. I want a clarification on this position as I can not counterargument both these statements without contradicting myself. I now ask Con if we can agree upon a criterion or standard that can determine what important means for this debate? A good criterion could be the answer to the question: IS IT IMPORTANT ENOUGH TO DO SOMETHING (green energy, trade caps etc. ) ABOUT IT? This standard/criterion can be refined but I think it is a good start. Disensus Con states that IPCC is biased, incompetent or has a secret agenda determined by bureaucrats. In the evidence presented [1] a scientist resigned from IPCC because he feared that IPCC MAY depart from scientific objectivity. He resigned because he considers that climate change science must remain politically neutral. Furthermore no one "imposed" any ideas on the scientist. I demand proof that there are imposed views on such a huge number of scientists. On the other hand it would be foolish for us to think that the discoveries of climate scientists have no political meaning. Besides the science there is an also a political battle. For the sake of our debate the two must be understood separately. Bearing this in mind I must point out that Con has pointed no secret agenda or motives for the IPCC to be biased. On the other hand I can point out a clear secret agenda (from the political perspective. There are people (like Con) that deny GW for the sake of finding the truth). One example is the editing of climate change reports by the White House [2]. The other two are the founding of The Marshal Institute by Exxon Mobile (the books quoted by Con are edited by the Marshal Institute) [3] and the relentless effort by the industry to promote climate change denial [4]. Their effort is nevertheless futile: first they argued that there is no GW, then that humans have no influence, than that the influence is insignificant etc. When comparing the "secret agenda" of IPCC and the quite obvious agenda of companies like Exxon it is clear who has more interest to mix politics and science and to misinform. Regarding the science arguments presented by Con, I will first point out that Con did not talk about anything about the super greenhouse effect on Venus that I have previously mentioned. This example shows that greenhouse gasses can produce quite dramatic effects. So from this perspective I consider that things are clear. With regards to many of the other arguments of Con, I must point out that his strategy is flawed. He will never win by pointing out a huge number of other causes that drive the climate even if they are more powerful than Co2. I clearly stated that I will prove that Co2 has a significant effect on GW. To make things more clear (bearing in mind the simplifications), let's consider t= f (sun, volcanoes, cosmic rays, clouds, particles, Co2 etc. ) + e. Con can win if he shows that: the system is not sensible to Co2 variations; Co2 variations cause a smaller temperature increase than the noise (e); Co2 receives a negative feed-back that counters its effect. By analogy, if there is a heart stroke risk of x because of eating to much fat you can't prove that this risk is smaller by showing that drinking also has a y hart stroke risk. Furthermore, in the first round I pointed out a positive feedback of Co2. Con dismissed this feedback saying that temperatures increased in the past and there was "something" that stopped this vicious circle. This is wrong because, as I showed in my proof, these are the highest levels of Co2 reached in 650 000 years [5]. Also, when there was warmer weather in the past there also was more vegetation to absorb the Co2. Now we have more Co2, warmer weather and less vegetation so the Co2 is not absorbed by anything at the rate by which it is produced. There is proof of this happening in the Carboniferous Era 300 million years ago [6]. Unfortunately we do not have giant forests to gather the solar heat and the Co2. The proof that shows that nowadays the Co2 levels are at a record level also dismisses the "all this happened before and it will happen again" argument made by Con. Con alleges that Co2 variations must have a multiplier. This is not true. It is enough for Co2 to create a 0.5 C increase for every 40% to have significant effects. Furthermore Con states that if climate would be a car than the Co2 would be an acceleration pedal. To be more exact we should consider climate a car with multiple pedals (sun, volcanoes, etc. ). Some pedals accelerate the car faster (sun), others accelerate the car slower (Co2). The fact that climate changed in less than 800 years simply shows that another more violent factor was involved not that Co2 theory is wrong. Further more the lag between temperature increase and Co2 has no significance. There will be a day of reckoning since Co2 is produced at a higher rate than it is absorbed in an ever increasing temperature that prevents Co2 absorption by oceans. Furthermore, the proof presented by Con itself acknowledges that there is some (although small) correlation between Co2 and temperature. From the fact that I reestablished the credibility of the IPCC reports, I have pointed out the clear bias of the two books presented by Con, I have pointed out the contradictions between the beginning and the end of his answer, I have showed that on Venus the greenhouse effect is really powerful, I have proven that Co2 rise is steady and has no negative feed-back, I conclude that my first position stands and that GW is man-made in a significant degree. Looking forward for another good round. [1] . http://sciencepolicy.colorado.edu... [2] . http://www.nytimes.com... [3] . http://www.ucsusa.org... - P. 32 [4] . http://www.newsweek.com... [5] . http://www.geocraft.com...

Global Warming is not significantly affected by human activity I will be arguing that global warming is not significantly impacted by human activity, and my opponent will be arguing that humans are the cause/have a big effect on global warming. Please begin your argument.

The sun drives the global climate It is the sun that is the driving force of our climate and so it makes sense that it has the biggest impact on our climate rather than anything that humans might be doing. The sun is therefore the most likely cause of global warming. Professor Henrik Svensmark, a physicist at the Danish National Space Center in Copenhagen argues that climate change is caused by solar activity.[[Louise Gray, 'Copenhagen climate summit: global warming 'caused by sun's radiation'', The Telegraph, 8/12/09, http://www.telegraph.co.uk/earth/copenhagen-climate-change-confe/6762640/Copenhagen-climate-summit-global-warming-caused-by-suns-radiation.html%5D%5D Solar activity, as determined by sunspot activity, is historically high being at its highest over the last 60-70 years for over 8000 years. Solar activity could affect climate by variation in the Sun's output or potentially through having an effect on cloud formation. Solanski et al. Sunspot numbers and cosmic ray fluxes... show correlations and anti-correlations with a number of reconstructions of the terrestrial Northern Hemisphere temperature, which cover a time span of up to 1800 years. This indicates that periods of higher solar activity and lower cosmic ray flux tend to be associated with warmer climate, and vice versa... This suggests that effects induced by cosmic rays may affect the long-term terrestrial climate. The positive correlation between the geomagnetic dipole moment and the temperature reconstructions provides further evidence favoring the cosmic ray influence on the terrestrial climate. [[I.G. Usoskin, S.K. Solanski, M. Schussler, K. Mursula, Solar activity, cosmic rays, and Earth’s temperature: A millennium-scale comparison, 1/10/05 http://cc.oulu.fi/~usoskin/personal/2004ja010964.pdf%5D%5D

Mankind Is the Main Cause of Global Warming I accept.

Humans are the main cause of global warming What is a greenhouse gas? Wikipedia says: A greenhouse gas is a gas in an atmosphere that absorbs and emits radiation within the thermal infrared range. This process is the fundamental cause of the greenhouse effect. The primary greenhouse gases in the Earth's atmosphere are water vapour, carbon dioxide, methane, nitrous oxide, and ozone. [1] 1. CO2 is increasing. The concentration of carbon dioxide (CO2) in Earth's atmosphere has reached 395 ppm (parts per million) as of June 2012 and rose by 2.0 ppm/yr during 2000"2009. This current concentration is substantially higher than the 280 ppm concentration present before industrial times, with the increase largely attributed to anthropogenic sources. [2] The burning of fossil fuels has caused CO2 levels in the atmosphere to rise from 280 ppm to 397 ppm. [1] 2. Methane is increasing, too. In 2010, methane levels in the Arctic was at 1850 nmol/mol, which is over twice as high as at any time in the 400,000 years before the industrial revolution. The Earth's atmospheric methane concentration has increased by about 150% since 1750, and it accounts for 20% of the total radiative forcing from all of the long-lived and globally mixed greenhouse gases (Excluding water vapour). [3] 3. Did the temperature rise? Statics say yes. The graph at [4] shows that it has risen by roughly 0.6 Degrees C. [1]http://en.wikipedia.org... [2]http://en.wikipedia.org... [3]http://en.wikipedia.org... [4]http://data.giss.nasa.gov...

That Humans Are Causing Climate Change The resolution is that humans have caused the modern climate change. However, most of my opponent's arguments either deals with the existence of global warming itself, or rules out (rather invalidly) other alternatives. He does very little to actually satisfy his burden of proof that humans are causing global warming. My arguments will be predicated on one simple assumption " that the vast majority of the claimed human impact is the result of greenhouse gas emissions. Humans Have Not Caused the Modern Global Warming There are many indicators that point to CO2 emissions not being the cause of the modern global warming. First, CO2 is actually a lagging indicator compared to temperature. As it turns out, temperature may be what's causing CO2 levels to rise. "The most recent study on this concluded that the results of their tedious but meticulous analysis led them to ultimately conclude that "the CO2 increase lagged Antarctic deglacial warming by 800 +/- 200 years. " There is also shorter correlations, but again, temperature seems to cause CO2 rise instead of the reverse. [1] This graph shows just one of the lags: [1] Second, according to the greenhouse effect, global warming should be starting from the lower atmosphere and moving to the surface (because the CO2 collects in the upper troposphere first). However, this is not happening. ". .. satellite and high-altitude balloon data confirm that the lower atmosphere is not trapping lots of additional heat due to higher CO2 concentrations. It is hard to know how fast the Earth's highly variable surface is warming, but it is warming faster than the lower atmosphere where the CO2 is accumulating. This is strong evidence that CO2 is not the primary climate factor. "[2] Here is a graph showing how the surface has warmed more than the troposphere: [1] (Blue line is lower troposphere temperature) Third, global warming is not starting at the poles like it should be, by the greenhouse theory. In fact, there has been general, relative cooling: "If the greenhouse theory were valid, temperatures in the Arctic and the Antarctic would have risen several degrees Celsius since 1940 due to the huge emissions of man-made CO2. .. Recently, a team led by the University of Chicago's Peter Doran published a paper in Nature saying, 'Although previous reports suggest recent continental warming, our spatial analysis of Antarctic meteorological data demonstrates a net cooling on the Antarctic continent between 1966 and 2000'. The data from 21 Antarctic surface stations show an average continental decline of 0.008 degrees C from 1978 to 1998, and the infrared data from satellites operating since 1979 show a decline of 0.42 degrees C per decade. David W. J. Thompson of Colorado State University and Susan Soloman of the National Oceanographic and Atmospheric Administration also report a cooling trend in the Antarctic interior. . .. report that satellite imaging shows increases in Southern Ocean sea ice parameters from 1978 to 1996 and an increase in the length of the sea-ice season in the 1990s. "[2] To illustrate, here is a picture of the southern hemisphere sea ice anomaly, which shows that southern sea ice is actually increasing: [3] Fourth, current levels of CO2 have very little effect on temperature. The greenhouse effect certainly exists, but it doesn't become linearly stronger with increasing amounts of CO2. CO2's effect on temperature is logarithmic, meaning that each additional increase has a smaller effect on the climate than the last. "The carbon that is already up in the atmosphere absorbs most of the light it can. CO2 only soaks up its favorite wavelengths of light and it's close to its saturation point. It manages to grab a bit more light from wavelengths that are close to its favorite bands but it can't do much more, because there are not many left-over photons at the right wavelengths. "[1][4] This chart shows approximately the effect that each additional increment of CO2 increase has on temperature: [4] Note how the pre-industrial to modern level increase has had less than a 0.2 C increase in temperature. Fifth and most importantly, the predicted "hot-spot" 10 miles above the tropics that would be a signature of CO2-induced global warming is absent. "The computer models show that greenhouse warming will cause a hot-spot at an altitude between 8 and 12 km over the tropics between 30 N and 30 S. The temperature at this hot-spot is projected to increase at a rate of two to three times faster than at the surface. However, the Hadley Centre's real-world plot of radiosonde temperature observations shown below does not show the projected CO2 induced global warming hot-spot at all. The predicted hot-spot is entirely absent from the observational record. This shows that atmosphere warming theory programmed into climate models are wrong. "[1] Here is the plot of predicted temperature changes due to CO2: However, here is the actual observed temperature changes: [1] The hot spot is completely missing, which is pretty much a knockout blow to the anthropogenic global warming theory. Even so, CO2 has not correlated well with the climate anyway. Throughout the past 600 million years, almost one-seventh of the age of the Earth, the mode of global surface temperatures was ~22C, even when carbon dioxide concentration peaked at 7000 ppmv, almost 20 times today's near-record-low concentration. Here is a graph showing CO2 concentrations versus temperature over the past 600 million years: [1] Note especially how high CO2 concentrations were earlier in Earth's history, reaching as high as 7000 ppmv. It was around 4500 ppmv during the very cold Ordovician era. Considering My Opponent's Arguments I was going to wait until the next round to consider his arguments, but after reading them, I thought I would discredit the majority of pro's arguments, as they aren't even worth arguing against. Arguments 1-3 are irrelevant - they don't show how human-emitted greenhouse gases have caused global warming. Argument 4 eliminates (rather invalidly) that the sun is not causing global warming " that still doesn't show that humans are causing global warming. Arguments 5 and 6 are relevant and I will consider them. Arguments 7 and 9-12 just show evidence for global warming " not anthropogenic global warming. Arguments 8, 13, and 14 will be considered. So essentially, only arguments 5, 6, 8, 13, and 14 are relevant to the resolution that pro made. All the rest either only prove global warming itself or demonstrate that humans have caused the increase in greenhouse gas concentrations, and so have no bearing on a debate considering anthropogenic global warming. I will consider those relevant arguments and those arguments only in the next round, along with any objections pro has to my own arguments. Sources [1]: . http://www.friendsofscience.org... [2]: Singer, S. Fred, and Dennis T. Avery: Unstoppable Global Warming: Every 1,500 Years [3]: . http://arctic.atmos.uiuc.edu... [4]: . http://joannenova.com.au...

The human effect on global warming is significant. I'm not sure how well I worded the debate resolution, so I will explain further. This is a scientific debate about whether humans are driving global warming and whether it is a problem. And so as not to cause any confusion, I hereby discredit Al Gore. Any arguments that cite Al Gore as a source should be ignored. Definitions Human effect: Effect caused by unnatural human actions; this includes sources such as factories and power plants but excludes sources such as natural respiration. Global warming: The trend of rapid global temperature increase since around 1975. CO2: Carbon dioxide. AGW: Anthropogenic global warming; global warming caused by human activities. I am making the case for the existence of AGW, while my opponent is trying to prove that AGW does not exist. ======================== Contention 1: Basic Scientific Argument ======================== The sun radiates electromagnetic waves onto the earth. They pass through the atmosphere, but are absorbed by the ground. When molecules on the ground absorb the electromagnetic radiation, they then re-emit it as infrared radiation. Infrared has a longer wavelength, so some atmospheric gases, called greenhouse gases – namely water vapor, CO2, and methane (CH4) – absorb it and turn it into thermal energy (a.k.a. heat). This traps heat, causing the earth's temperature to increase. Because of the greenhouse effect, the more greenhouse gases there are, the hotter it gets. This effect isn't much like a greenhouse, but I will nonetheless use the term. For hundreds of thousands of years, CO2 levels remained in the 180 to 300 ppm (parts per million) range [1]. But as of 2007, CO2 levels were at 390 ppm [2]. The environment was relatively stable for hundreds of thousands of years, so why the sudden change? Human emissions can only be responsible. Humans have been emitting CO2 in vast quantities since the mid-70's: our cars emit it, our factories emit it, even our homes emit it. ======================== Contention 2: Scientific Consensus ======================== It is important to remember that science is not a democracy. But if nearly all scientists agree on something, it is probably correct. And nearly all scientists support AGW. I: Scientific Societies Many scientific societies have advocated for AGW. At this time, it is important to remember that scientific societies are not advocacy groups. But these societies found AGW so important that they felt they had to endorse it. The national scientific societies of 21 countries have endorsed AGW: Australia, Belgium, Brazil, Caribbean, Canada, China, France, Germany, India, Indonesia, Ireland, Italy, Japan, Malaysia, Mexico, New Zealand, Russia, South, Africa, Switzerland, United Kingdom, United States [3]. The following societies have also endorsed AGW: Network of African Science Academies, National Research Council, European Science Foundation, World Meteorological Organization, Federation of American Scientists, American Meteorological Society, American Association for the Advancement of Science [4]. This is far from a complete list, but is meant to give an idea of how many scientists support AGW. This list represents hundreds of thousands of scientists. II: Peer-Reviewed Papers Perhaps more important than the endorsement of scientific societies is peer-reviewed papers. In 2004, Science magazine conducted a search for scientific papers on the topic of global warming [5]. They searched through all papers with the keywords "climate change", for a total of 928 scientific articles. Here is a quote from [5]: {quote} The 928 papers were divided into six categories... Of all the papers, 75% fell into the first three categories, either explicitly or implicitly accepting the consensus view; 25% dealt with methods or paleoclimate, taking no position on current anthropogenic climate change. Remarkably, none of the papers disagreed with the consensus position. Admittedly, authors evaluating impacts, developing methods, or studying paleoclimatic change might believe that current climate change is natural. However, none of these papers argued that point. This analysis shows that scientists publishing in the peer-reviewed literature agree with IPCC, the National Academy of Sciences, and the public statements of their professional societies. Politicians, economists, journalists, and others may have the impression of confusion, disagreement, or discord among climate scientists, but that impression is incorrect. The scientific consensus might, of course, be wrong. If the history of science teaches anything, it is humility, and no one can be faulted for failing to act on what is not known. But our grandchildren will surely blame us if they find that we understood the reality of anthropogenic climate change and failed to do anything about it. Many details about climate interactions are not well understood, and there are ample grounds for continued research to provide a better basis for understanding climate dynamics. The question of what to do about climate change is also still open. But there is a scientific consensus on the reality of AGW. Climate scientists have repeatedly tried to make this clear. It is time for the rest of us to listen. {/quote} ======================== Contention 3: Risk Management ======================== Let's assume that it is equally likely that global warming is man-made and that it is natural. In these circumstances, what are the worst-case scenarios? We assume that global warming is man-made, when it is actually natural. Worst-case scenario, our futile efforts cause an economic crash and we go into another great depression. Now let's say we assume that global warming is natural, when it is actually man-made. The benefit here is that we don't spend any time worrying about how we're all going to die. The bad news is, the human race is in a complete wreck. Expensive natural disasters have destroyed the economy. Millions are homeless and jobless, and thousands are dead. Not so good. So when these two cases are equally likely, it is far riskier to assume that global warming is natural. Actually, it's arguable that the economic crash caused by a shift in energy sources was actually inevitable, and even lessened. If we are forced to drive efficient cars and use renewable energy sources, it will be harmful to some big energy companies. But we would have run out of fossil fuels eventually. When we run out of fossil fuels, it will be heavily devastating. But if we make the shift now, because of global warming, we can make it slow enough so that big corporations have time to adapt. Additionally, "green" technologies are looking to be a sound investment. Developing them may fuel the economy more effectively than many current technologies. Assuming that global warming is man-made, far from ruining the economy, may actually help it. Even if we were 90% certain that global warming is natural, we should still take precautionary steps to prevent global warming. Even if the chance of mass destruction is only 10%, it's still 10%. We'd be playing Russian Roulette with the planet. And Russian Roulette never ends well. *** I thank my soon-to-be opponent and look forward to a fun debate. *** References [1] http://www.newscientist.com... [2] http://www.newscientist.com... [3] http://logicalscience.com... [4] http://www.aaas.org... [5] http://www.sciencemag.org...

Mankind Is the Main Cause of Global Warming C1) Climate Sensitivity & Feedbacks My first contention is to demonstrate CO2 has effects in rising the mean land-sea temperature. Climate sensitivity is the level of hypothetical temperature rise if the concentration of atmospheric CO2 would double. [1] It is not a much debated fact that the temperature rise would be by 1 degrees C. This, though, can be amplified by feedbacks. Positive feedbacks amplify the temperature rise, and negative feedbacks diminish the temperature rise. A study published in Climate Research proved that the mean climate sensitivity is approximately 1 to 1.6 degrees Celsius due to the level of positive feedbacks. [2] Another significant body of research notes that climate sensitivity is likely much higher. A review of the evidence in 2008 finds that mean climate sensitivity is 3 degrees C, with a range of 2 – 4.5 degrees C. Nearly every study taken discovers the average climate sensitivity is 3 degrees C. [3] The above graph demonstrates the effect of upper fluctuations in equilibrium temperature via. feedbacks. [4] The graph shown above was from a 2007 research that places approximate mean climate sensitivity to double CO2 concentration at around 2.5 - 3. [5] It is a well known fact that industrial emissions have major impact on the concentration levels of carbon dioxide in the atmosphere. “In pre-industrial times over the last 10,000 years, CO2 was relatively stable at around 275 to 285 parts per million. Over the last 250 years, atmospheric CO2 levels have increased by about 100 parts per million. ” [6] Thus, human-caused amplified climate sensitivity affects mean land-sea temperature. C2) Human-Emitted Greenhouse Gases There is a documented rise in CO2 concentrations in the atmosphere over the last 250 years, with a 100 ppm increase in industrial times *alone*, versus a 50 ppm increase from 9,750 years prior. Below is a graph showing the rise in atmospheric CO2 concentrations. [7-8] It is a well-known fact that majority of increase in atmospheric CO2 concentrations is caused by humans. This is because of the sudden hike during industrial times alone. [6] CO2 is known to form an atmospheric layer and trap heat within the atmosphere, thus increasing the mean temperature via. the greenhouse effect, wherein insolation and terrestrial radiation are both trapped within the atmosphere. [9-10] Below is a graph showing a correlation in the rise in temperature and rise in atmospheric CO2 concentrations. “[T]here is a close correlation between Antarctic temperature and atmospheric concentrations of CO2 (Barnola et al. 1987). The extension of the Vostok CO2 record shows that the main trends of CO2 are similar for each glacial cycle. Major transitions from the lowest to the highest values are associated with glacial-interglacial transitions. During these transitions, the atmospheric concentrations of CO2 rises from 180 to 280-300 ppmv (Petit et al. 1999). The extension of the Vostok CO2 record shows the present-day levels of CO2 are unprecedented during the past 420 kyr. ” [11] The CO2-temperature correlation is also influenced by CO2’s impact on solar radiation itself. In the Cenozoic era, there was a rise in solar activity due to CO2. “Because Earth absorbs about 240 W/m^2 of solar energy, that brightness increase is a forcing of about 1 W/m^2. This small linear increase of forcing, by itself, would have caused a modest global warming through the Cenozoic Era. " The CO2 levels caused a much higher forcing. In contrast, atmospheric CO2 during the Cenozoic changed from at least 1000 ppm in the early Cenozoic to as small as 170 ppm during recent ice ages. The resulting climate forcing, as can be computed accurately for this CO2 range using formulae in Table 1 of Hansen et al. (2000), exceeds 10 W/m^2. It is clear that CO2 was the dominant climate forcing in the Cenozoic. ” [12] There is proof that it is warmer now than any year of human life since 1400. This is depicted in the graph below. [13] Conclusion Thus, I have presented two valid contentions as to why global warming is man-made. Con must present contentions of their own in the next round and defend theirs in the round after. The resolution is resoundingly affirmed. Sources 1. . http://tinyurl.com... 2. . http://tinyurl.com... 3. . http://tinyurl.com... 4. . http://tinyurl.com... 5. . http://tinyurl.com... 6. . http://tinyurl.com... 7. . http://tinyurl.com... 8. . http://tinyurl.com... 9. . http://tinyurl.com... 10. . http://tinyurl.com... 11. . http://tinyurl.com... 12. . http://tinyurl.com...

Climate Change is real and caused by humans All points extended.

Climate Change is real and caused by humans All points extended.

Global Warming is not significantly affected by human activity My opponent points out that my response was significantly shorter in an attempt to make it seem weaker. Length of the response has nothing to do with the quality of it. It's not about the amount of words in your argument, it's about the amount of argument in your words. The main reason why my opponent had such a large argument is because he decided to explain the entire process of global warming, which was completely unnecessary. In my opponent's second paragraph, he addresses the fact that we "should've" had an ice age, but we didn't. In this way, my opponent's attempts to debunk my claims. I do not see the point of the paragraph. It is evident from the graph that I provided that cool-downs and peaks do not occur on a perfect 100,000 year schedule, and there are variations, plus or minus 10,000-15,000 years. My opponent also says that "we are heading towards another Ice Age in the opponent's view". My argument never centered around Ice Ages. Yes, I believe we are heading towards an Ice Age that will only occur in several more millenniums, but that is not my argument. My argument is that global warming is a naturally occurring process which humans have little to no control over. My opponent must have the graph wrong, because the last ice age occurred less that 50,000 years ago. If so, how in the world was there supposed to be an ice age in the 1950s? Next, my opponent addresses the CO2 concentrations and shows a little cloud diagram. Although humans pump tons of CO2 into the atmosphere, global temperatures are not changing proportionally. According to my opponent's diagram, volcanic CO2 emissions reach up to 319 million tonnes per year, while human-burned fossil fuels produce 29 billion tonnes a year. That means that humans put out at least 90 times more CO2 into the air than nature does. If we are the cause of global warming, then logically, global temperatures would increase by an enormous factor. But do they? The graph that I provided clearly shows that there has not been any earth-shattering increase in temperature as there should have been when humans are increasing the amount of CO2 from its natural levels by a factor of 90. The rest of my opponent's argument is also different facts about how much CO2 humans are putting into the atmosphere. I will note that my opponent pays no attention to temperature itself, but only focuses on the changes in CO2 amounts. We are not arguing about CO2, we are arguing global warming, which is the change in temperature, not CO2 concentration. As I proved in the above paragraph, global temperature is not changing proportionally to the amount of CO2 increase, meaning that although there may be a correlation, it is not strong enough to base your entire argument on it. It so happens that CO2 is not the number 1 greenhouse gas. Water vapor is. Water vapor accounts for up to 70% of the greenhouse effect. Water vapor is everywhere and when its amount increases, so does the global temperature. While CO2 also plays a role, it is minuscule compared to water vapor and humans have no effect on the amounts of water vapor in the atmosphere. . http://www.popsci.com... This debunks my opponent's entire argument. Something else that I would like to note is that most/all the graphs my opponent uses are using information about the last 100-200 years. Of course, on those graphs the temperature is actively increasing with CO2 because of how "zoomed in" they are. If you look on a broader scale (the graph that I provided), it is obvious that CO2 levels cycle just like global temperature, and my opponent simply zoomed in on the peak, so it seems like it is forever increasing. I will now recap my points and show that humans have little to no impact on global warming. 1. Even though CO2 concentrations have increased by a factor of 90, the temperature has not increased anywhere near that amount, suggesting that there is not such a strong relationship between CO2 and global temperatures. While CO2 does make a difference, the correlation and effect is not strong enough to make any conclusions and base entire arguments on it. 2. The cycle of global warming followed by ice age, followed by another global warming has been going on for hundreds of thousands of years, and we currently reaching the peak of temperature. Humans have little to no impact on this naturally occurring process. 3. CO2 is not the "biggest" greenhouse gas, water vapor is. Meaning that with an already weak correlation between CO2 and temperature, CO2's impact was just proven even smaller because it is not the only nor most effective greenhouse gas. Water vapor accounts for up to 70% of the greenhouse effect, meaning CO2 accounts for less than 30% of it (because there are many other greenhouse gases such as methane). As a result of these three main points, I believe it is reasonable to conclude that humans have no significant impact on global temperatures. Thank you for the good argument.

There is no anthropomorphic global warming "In your case, you argue that co2 is a green house gas and can be proven to be a warming agent. I do not disagree. Where I disagree is whether or not this co2 is causing today's warming. In most historical episodes of warming, co2 trails temperature. If it was a forcing agent, one would expect the exact opposite. Co2 has been much higher in the past and temperatures were lower: http://www.nolanchart.com...... "In fact, 450 million years ago when we were in the depths of the coldest period the Earth has had in half a billion years, CO2 levels were 10 times above today's! Even using the last century as evidence for a dependent relationship is meaningless. 65% of the warming this century occurred in the first three decades, and then, while CO2 levels continued to rise, temperatures fell for four decades in a row." ============================================================================== http://environment.newscientist.com... Ice cores from Antarctica indicate that at the end of recent ice ages, the concentration of carbon dioxide in the atmosphere started to rise only after temperatures had begun to climb. There is uncertainty about the timings, in part because the air trapped in the cores is younger than the ice, but it appears the difference might at times have been 800 years or more. This shows that rising CO2 was not the trigger that caused the initial warming at the end of these ice ages – but no climate scientist has ever made this claim. It certainly does not challenge the idea that increases in CO2 heats the planet. CO2 is a greenhouse gas because it absorbs and emits frequencies of infrared radiation. Physics tells us that gases with this property trap heat radiating from the Earth, that the planet would be a lot colder if this effect was not real and that adding more CO2 to the atmosphere will trap even more heat. Furthermore, CO2 is just one of a group of greenhouses gases, and greenhouse gases are just one of many factors affecting the climate. There is no reason to expect a perfect correlation between CO2 levels and temperature in the past: if there is a big change in another climate "factor", the correlation will be hidden. It takes around 5000 years for an ice age to end and, after the initial 800 year lag, temperature and CO2 concentrations in the atmosphere rise together for a further 4200 years. What seems to have occurred at the end of recent ice ages, some factor - most likely orbital shifts - caused a rise in temperature. This led to an increase in CO2, resulting in further warming that caused more CO2 to be released and so on: a positive feedback that amplified a small change in temperature. At some point, the shrinking of the ice sheets further amplified the warming. Models indicate that rising greenhouse gases, including CO2, explains for about 40% of the warming as the ice ages ended. The figure is uncertain because it depends on how the extent of ice coverage changed over time, and there is no way to pin this down precisely. The ice ages show that temperature can determine CO2 as well as CO2 driving temperature. Sceptics - not scientists - have seized upon this idea and claim that the relation is one way, that temperature determines CO2 levels but CO2 levels do not affect temperature. Higher temperatures lead to more CO2 and more CO2 leads to higher temperatures. There are multiple limiting factors that kick in, the most important being that infrared radiation emitted by Earth increases exponentially with temperature, so as long as some infrared can escape from the atmosphere, at some point heat loss catches up with heat retention. To put it simply, we have altered the way natural feedbacks systems operate via the way we change the planet's surface and atmosphere. That is the difference to "450 million years ago". This is the error in your argument. You are basing climate change purely on CO2 entering the atmosphere. Climate change is vastly more complex than that, and human influence is equally more diverse than that simple aspect. However since your sole argument is based on CO2 we will continue. Ice cores show that carbon dioxide levels in the atmosphere have remained steady between 180 and 300 parts per million for the past half-a-million years. In recent centuries, however, CO2 levels have risen sharply, to at least 380 ppm. Human emissions of CO2 are small compared with natural sources. The fact that CO2 levels have remained steady until very recently indicates that natural emissions are usually balanced by natural absorptions. Now more CO2 must be entering the atmosphere than is being absorbed via carbon "sinks". The consumption of terrestrial vegetation by animals and by microbes (rotting) emits about 220 gigatonnes of CO2 every year, and respiration by vegetation emits another 220 Gt. These amounts are balanced by the 440 Gt of carbon dioxide absorbed from the atmosphere each year as land plants photosynthesise. Likewise, parts of the oceans release about 330 Gt of CO2 per year, depending on temperature and rates of photosynthesis by phytoplankton, but other parts usually soak up just as much and are now soaking up slightly more. Human emissions of CO2 are now estimated to be 26.4 Gt per year, up from 23.5 Gt in the 1990s http://www.ipcc.ch... So are we to blame for the CO2 increase? There are several lines of evidence. Fossil fuels were formed millions of years ago. Therefore they contain virtually no carbon-14. Because this unstable carbon isotope, formed when cosmic rays hit the atmosphere, it has a half-life of around 6000 years. So a dropping concentration of carbon-14 can be explained by the burning of fossil fuels. Studies of tree rings have shown that the proportion of carbon-14 in the atmosphere dropped by about 2% between 1850 and 1954. After this time, atmospheric nuclear bomb tests ruined this method by releasing large amounts of carbon-14. Additionally fossil fuels contain less carbon-13 than carbon-12, compared with the atmosphere. These fuels are derived from plants, which preferentially take up the more common carbon-12. The ratio of carbon-13 to carbon-12 in the atmosphere and ocean surface waters is steadily falling, clearly showing that more carbon-12 is entering the atmosphere. Frankly your argument so far is based solely on the link to CO2 and temperatures. CO2 is not the only greenhouse gas neither is fossil fuel burning the sole reason for their increase. Deforestation removes natural carbon sinks, draining swamps releases large amounts of stored CO2 and methane. Similarly greenhouse gases are not the sole reason climate change is occurring. Factors relate and feed off each other; warmer air, warmer ocean currents etc. CO2 feeds off temperature, temperature feeds off CO2. It is flawed to say that humans are the sole reason for climate change because clearly it plays to natural systems. It is equally mistaken however to say that humans have had no substantial impact at all. Which brings us to "it is not true that anything that can cause warming is in fact causing current warming." that being self refuting rubbish. Clearly it has a cause(s). Recommended: http://www.ipcc.ch...

Anthropogenic climate change. Acknowledgement of opposing evidenceI shall first bring up some evidence in favor of anthropogenic climate change. One may wonder why I would do this when I am arguing against anthropogenic climate change, but it’s really simple: I do this in order to provide the opposing side some representation and then I will present my side to refute that side’s argument. That is the most logical way of debating, and if you ignore evidence when it is available to you, that is a cherry-picking fallacy. The main evidence of anthropogenic climate change, is the increased levels of CO2 emissions within the past couple of centuries. It is believed that irreversible effects are occurring now and into the future due to increased CO2 emissions, and that this CO2 emission increase is due to primarily human activity [1]. In fact, in this study, it is shown that if humans were to cut all CO2 emissions the CO2 in the atmosphere would linger still and still cause more warming even if it were all put to an end. [1] There are of course plenty of other studies that show this as well. Refuting the scientific consensusThere is often stated that 97% of climate scientists agree that anthropogenic climate change is real[2]. However, it is a fallacy to trust the words of authorities on the matter without considering the evidence. In a study conducted by John Cook et al, the same source that my opponent has cited, it was found that majority(66.7%) of studies in relation to anthropogenic climate change were either neutral or inconclusive.[3] One must wonder why 97% of climate scientists are of the opinion anthropogenic climate change is real when the majority of evidence out there is inconclusive and there is some scientific evidence(.7% of studies out there) that anthropogenic climate change is not real, which I shall point out later. In science, something needs to be tested over and over again and achieve the same results in order to conclude something off of it. The fact that U32; of anthropogenic climate change studies come up with inconclusive or neutral results indicates that we actually don’t understand the effects humans have on climate change, and the scientists are assuming we do by taking the 32% of times that it proved anthropogenic climate change as fact, when majority of the time there is no conclusion to be made. Therefore, 97% of climate scientists, are, in fact, acting unscientifically in this case. Reiterating previous debate pointsIn a previous debate with the same user, it was established that 3.225% of all CO2 emissions are caused from humans by unnatural causes. [4] In addition, the global temperature for over the past 136 years has only gone up by about 1 degree fahrenheit[1]. These two facts suggest that if humans have had impact on the climate, it is hardly anything to be worried about at all. Problems with CO2 emissions claimsSince there may be an increase in natural CO2 emissions, it is hard to conclude that the CO2 emissions by humans is what is causing the warming specifically. All variables need to be taken into account, which the study in my second paragraph under “Acknowledging opposing evidence” that claims anthropogenic climate change happens from CO2 emissions by humans, doesn’t take into account the natural CO2 emissions, the activity of the sun, or anything else that could be leading to warming of the earth. In addition, it has been found in one study by Willie Soon et al, that CO2 emissions rising often follows temperature rise, and not always the other way around [5]. If it was as simple as CO2 rises, and therefore temperature rises due to it, then the reverse should not be happening where temperature rises and then CO2 rises. It was also found that CO2 forcing effects on seasonal temperature to be inconclusive, particularly since CO2 emissions cause warming at first, but the warming causes more evaporation of water and thus more clouds and humidity, which lead to a cooling effect, the net effect is not much change in the overall temperature [5] Next, another study performed by G. V Chilingar et al found that “Even significant releases of the anthropogenic carbon dioxide into the atmosphere do not change average parameters of the Earth’s heat regime and the atmospheric greenhouse effect. Moreover, CO2 concentration increase in the atmosphere results in rising agricultural productivity and improves the conditions for reforestation. Thus, accumulation of small additional amounts of carbon dioxide and methane in the atmosphere as a result of anthropogenic activities has practically no effect on the Earth’s climate.” In another comprehensive study on global temperature rises by Patrick J. Michaels et al, it was concluded from “observations of atmospheric CO2 buildup and global CO2 emissions... that lead to exponential warming... is not based upon the reality of recent decades.” Many of the models scientists have come out with to show that CO2 rises cause exponential warming, are not reflective of what has actually been happening in the world, and the warming in the world is much more linear. Problems in general with anthropogenic climate changeWhile I could continue to talk about all of the evidence against anthropogenic climate change, I shall instead provide a link to over 90 peer-reviewed scientific articles that show problems with anthropogenic climate change; there are many and various problems with it ranging from how CO2 doesn’t actually affect temperature in the long-term since it balances out when water is evaporated by the initial warming, to problems with climate models, to what should have been expected to result from anthropogenic climate change not actually happening. [7]Due to all of these issues listed above in this category and the previous 3, it is difficult to believe the climate scientists who claim anthropogenic climate change is a reality, when, as far as I’m aware, they have not addressed the above issues outlined. Inconclusive results and the default positionBecause as mentioned before, that majority of the studies done into anthropogenic climate change resulted in inconclusive or neutral results, the default position should be that anthropogenic climate change does not exist. Just as believing a god doesn’t exist is the default position when there is not conclusive evidence for or against a god, or majority of the evidence is inconclusive or neutral, so would then the position on anthropogenic climate change have the default position of not believing in it. Sources:[1] http://www.pnas.org... [2] http://climate.nasa.gov... [3] http://iopscience.iop.org...[4] http://www.debate.org... [5] http://articles.adsabs.harvard.edu...[6] http://adsabs.harvard.edu... [7] https://skepticalscience.com...

Global warming is likely (and mostly) anthropogenic To not confuse other members, I would like to clarify that I am devils advocating. I will be presenting similar ideas and data points as presented in the Rational Wiki article, but will expand on their current content [1]. 1. The Earth's atmosphere keeps the planet much warmer than it would be without an atmosphere. Unless my opponent disagrees, I will proceed to the next point. 2. The main gases which contribute to this are carbon dioxide, methane and water vapor. Collectively these are called greenhouse gases. Unless my opponent disagrees, I will proceed. 3. The ability of these gases to act as greenhouse gases can be shown in a laboratory. Although my opponent likely agrees, I would like to expand on this somewhat. CO2 is a greenhouse gas and causes some warming. My opponent will likely argue, if he disagrees with this point, that the CO2 effect is minimal or the climate system deals with this through negative climate feedbacks. However, the empirical and peer-reviewed literature obliterates these claims. Recent studies have ranked CO2 the largest factor in the modern warming by far (figure right), and that the feedbacks amplify this initial greenhouse warming substantially (left) [2]. The National Research Council has come to similar conclusions noting, “A strong, credible body of scientific evidence shows that climate change is occurring, is caused largely by human activities, and poses significant risks for a broad range of human and natural systems”. [3] Former research by Mike Lockwood, who used to be a skeptic and favor a celestial origin of climate change, has published studies noting that the main forcing in climate is human emissions—namely, CO2—humans cause at least 75% of the modern warm period [4]. These laboratory measurement’s seem to be at work in our atmosphere. 4. The quantity of these greenhouse gases in the atmosphere has increased sharply since the Industrial Revolution, and their concentration continues to do so. My opponent likely agrees, again. 5. The concentration of these gases has increased as a consequence of human activity. Skeptic scientists also agree with this—all measurement’s here (well, nearly all) indicate that most of the CO2 increase is due to manmade sources. 6. The temperature of Earth's atmosphere has been increasing and continues to increase. The fact that we are in a warming phase is uncontroversial [5][6]. 7. The increase in global temperature correlates with the increases of greenhouse gases. This is also a fact. Indeed, independent measurements have proven that long wave radiation is exiting at a slower pace indicating greenhouse gases, to some extent, have warmed the earth. Most likely very significantly [7]. Nearly every estimate shows excellent correlation between the two (co2 vs temperature) [8]. Other data using CO2 measurement’s from Mauna Loa vs global temperatures has found a remarkably close correlation between CO2 and Climate [9]. Further analysis of paleoclimate noted CO2 has amplified past warmings [10]. --- That is it, for now. 1. . http://rationalwiki.org... 2. . http://www.giss.nasa.gov... 3. . http://nas-sites.org... 4. . http://rspa.royalsocietypublishing.org... 5. . http://www.ipcc.ch... 6. . http://climate.nasa.gov... 7. . http://www.giss.nasa.gov... 8. . http://www.skepticalscience.com... 9. . http://public.econ.duke.edu... 10. . http://www.realclimate.org...

Humans Cause Global Warming I am devils advocating this debate. I will argue human emissions are causing current climate change.

Resolved: Human Activity Is a Significant Factor in Global Warming on Planet Earth. Same

Climate Change is driven by human CO2 emissions My opponent as PRO has the BOP, this shall not be negotiated. Definitions: CO2 emissions: "emissions of CO2 from burning oil, coal and gas for energy use. Carbon dioxide also enters the Atmosphere from burning wood and waste materials and from some industrial processes such as cement production. Emissions of CO2 from these sources are a relatively small part of global emissions and are not included in these statistics."[1] In other words, it is a naturally occurring gas that supposedly causes the majority of global warming. ==> What we argue <== PRO (my opponent) argues these CO2 emissions cause global warming (which we assume exists). CON argues that global warming is primarily controlled by human emissions. In this debate I must provide a time frame. The little ice age - present. 1st round acceptance by PRO. No abusive arguments please. [1] http://www.wikiprogress.org...

Global Warming Exists (2) IntroductionThanks Steve for your arguments. Technically the first round was solely for acceptance, but we'll make do with it. I am commiting a grievous sin of my own by copying my argument from a different debate so I suppose we're even.For my argument I would first off like to define a few terms as it is likely that they will be used several times by both debaters. Global warming: a gradual increase in the overall temperature of the earth's atmosphere.Greenhouse effect: the trapping of the sun's warmth in a planet's lower atmosphere.Carbon Dioxide (CO2): a colorless, odorless gas produced by burning carbon and organic compounds and by respiration.Fossil Fuels: a natural fuel such as coal or gas, formed in the geological past from the remains of living organisms.With the definitions aside, let the debating begin!How does the greenhouse effect work? Before I begin defending the premise defined in the first round, I would like to clarify how the process called the greenhouse effect works. This is essential to the topic of global warming, as the greenhouse effect is the process which warms the planet, especially during the nigh time. When sunlight reaches the earths atmosphere it changes into thermal radiation. Most of this thermal radiation is reflected off back into space due to the earth's atmosphere, however some manages to enter the planet. Once it reaches the atmosphere, it comes down to the surface, still as light, and is converted into energy through the process of photosynthesis. Eventually this energy is transferred from the plant to a primary or secondary consumer when the plant/producer is eaten by the consumer. Due to a concept called the 10% rule, almost all of the energy (90%) is lost during the transfer from producer to consumer and is radiated back into the atmosphere as heat [1]. Some of this heat manages to leave the atmosphere and goes off to space where it becomes essentially useless. A small percent of the heat, however, is trapped by the greenhouse gases (such as CO2, CH4, N2O, etc) and is kept in the atmosphere [2]. This is important because during the nigh time when the sun is not providing heat, the heat preserved by the greenhouse gases keep the planets surface warm [3].This generally should be considered a good thing, however in this case there can be to much of a good thing. Due to the fact that there is now an abundance of greenhouse gases in the atmosphere, especially carbon dioxide, too much heat is being trapped in the atmosphere and as a result global temperatures have risen. I will attempt to prove that the reason for this abundance of greenhouse gases and as a result increased global temperatures is a result of human actions, and it is not a "natural" occurrence. Graph A shows the basic process of the greenhouse effect. Graph A: Argument structureMy argument will follow this basic format: P1) The increase of carbon dioxide in the atmosphere is a result of human actions. P2) Carbon dioxide in the atmosphere causes an increase in global temperatures. P3) Therefore human beings are responsible for global warming. P1) The increase of carbon dioxide in the atmosphere is a result of human actions. This is not a very difficult subject to defend and consequently it is not a very controversial subject, therefore I will be brief. Since the industrial revolution in the mid 1800's more and more carbon dioxide has been released into the atmosphere. Graph B shows the rapid increase in carbon emmisions starting in 1850. Graph B: The reason for this is obvious, due to rapid increasing of industry and technology, burning of fossil fuels has become more and more frequent. Due to the fact that the burning of fossil fuels emits carbon dioxide into the atmosphere, it is also obvious that the increased amount of carbon dioxide in the atmosphere is a result of human activity. P2) Carbon dioxide in the atmosphere causes an increase in global temperatures. This is a much more controversial subject, and therefore I will spend the majority of my argument in this section. Given that the greenhouse effect states that greenhouse gases trap heat, and re radiate it in all directions, as shown in Graph A, it would be easy to make the assumption that if there is more carbon dioxide in the atmosphere there would be less long wave radiation (the type of heat that CO2 absorbs) being emitted into space and more infrared radiation being emitted back to the earth. This, as a result, would heat up the world and cause global warming. To prove this hypothesis, NASA launched the IRIS satellite in 1970 to record the amount of long wave radiation being emitted into space over a 26 year period [4]. What they found supported the hypothesis that less long wave radiation was being emitted into space and as result their was more infrared being contained in the earth. Graph C displays the results of the experiment.Graph C: This graph is an infrared spectrum and it shows the frequencies of infrared light (800 to 1600 cm-1). The graph has multiple greenhouse gases (such as CO2 and CH4) and based on their position on the graph, it determines the frequency of infrared light that they absorb. For example CO2 is at the far end of the spectrum because it absorbs lower frequency light than CH4 (methane), which is at the far end of the spectrum. The graph shows the difference of the amount of infrared radiation that is being absorbed by the various greenhouse gases between 1970 and 1996. Due to the fact that there is a greater variation in both CO2 and CH4 it shows that there is more radiation being absorbed by those two gases. In simpler terms, this shows that there is more heat being trapped by carbon dioxide and methane then there used to in the past, and therefore as a result global warming is a result of the carbon dioxide and methane in the atmosphere. If these gases are the cause of global warming than it can also be determined that human beings are the cause of global warming because they are the ones that are emitting the CO2 and CH4 into the atmosphere. Moving on to the next graph, Graph D is representing the amount of infrared radiation at the earth's surface. Graph D: This graph is somewhat less complex than Graph C (thankfully). What it is representing is once again the infrared radiation spectrum (600-1800 cm-1) and the greenhouse gases that trap the radiation at certain spectrums. CO2 is found and approximately 800 cm-1 and consequently there is a much higher amount of infrared radiation at 800 cm-1 at the earths surface than there is of any other wave frequency. What this means is that carbon dioxide is responsible for the majority of the heat being contained in the earth. By extension, this means that carbon dioxide is causing global warming and that it is once again human beings fault due to the fact that we are the ones emitting the CO2 into the atmosphere. Now moving on to the final graph. Graph E is showing both the amount of carbon dioxide in the atmosphere and also the global temperatures. Graph E: What Graph E is conveying is that there is a huge amount of carbon dioxide in the atmosphere currently, much higher than there has ever been in the past. Now there are three important things to note in this graph. One is that throughout the course of history, whenever global temperatures increased, the carbon dioxide levels in the atmosphere had increased as well. This allows us to reach the conclusion that the more carbon dioxide in the atmosphere, the higher temperatures will be. The second thing to note is that in none of the historical situations did global temperatures increase at the exact same time that the carbon dioxide levels. In every situation the temperatures took several years to rise following an increase in carbon dioxide levels. This is important because it shows global warming skeptics, like my opponent, that global temperatures will not increase right away. This is why temperatures have not increased so rapidly yet, however given the trend of this graph they are certain to increase in the near future. The final thing to note is the huge amount of carbon dioxide in the atmosphere today. In no situation in history has their been such a high amount of carbon dioxide in the atmosphere, and the only explanation for why this is is human activity. Global warming skeptics claim that we cannot know that it is human being fault for global warming, however this chart shows the contrary. P3) Therefore humans are responsible for global warmingI have proved that carbon dioxide is the primary reason for why their has been increases in global temperatures as of late. This negates skeptics major arguments about why global warming is not human beings fault because it is clear that carbon dioxide emittions are due to human beings, and therefore it can be concluded that human beings are the cause of global warming. Sources[1] http://en.wikipedia.org......[2] http://www.epa.gov......[3] http://hyperphysics.phy-astr.gsu.edu......[4] http://www.skepticalscience.com......