Man-Made global warming exists* and poses a serious threat to humanity.

RebuttalsThe Greenhouse potential of CO2This is actually an excellent point made by my opponent. There are two problems with it, though. A) Man realeases many other, potent, greenhouse gases. B) Man contributes to global warming in more ways than just producing greenhouse gases. (A) The greenhouse gamut of gasesMan produces more than just CO2 grenhouse gases. Man is also directly responsible for CH4 (methane) emissions, N20 (Nitrous Oxide) emissions, and Chlorofluorocarbons ("F" Gases). Here is a chart depicting the full impact of these gases. • Carbon dioxide (CO2). Accounts for around three-quarters of the warming impact of current human greenhouse-gas emissions. The key source of CO2 is the burning of fossil fuels such as coal, oil and gas, though deforestation is also a very significant contributor. • Methane (CH4). Accounts for around 14% of the impact of current human greenhouse-gas emissions. Key sources include agriculture (especially livestock and rice fields), fossil fuel extraction and the decay of organic waste in landfill sites. Methane doesn't persist in the atmosphere as long as CO2, though its warming effect is much more potent for each gram of gas released. • Nitrous oxide (N2O). Accounts for around 8% of the warming impact of current human greenhouse-gas emissions. Key sources include agriculture (especially nitrogen-fertilised soils and livestock waste) and industrial processes. Nitrous oxide is even more potent per gram than methane. • Fluorinated gases ("F gases"). Account for around 1% of the warming impact of current human greenhouse-gas emissions. Key sources are industrial processes. F-gases are even more potent per gram than nitrous oxide. (1) The emissions for CO2 from man alone may not account for the upward trend, but it is certainly not natural cycles. National Geographic writes, "Scientists have spent decades figuring out what is causing global warming. They've looked at the natural cycles and events that are known to influence climate. But the amount and pattern of warming that's been measured can't be explained by these factors alone. The only way to explain the pattern is to include the effect of greenhouse gases (GHGs) emitted by humans. " (2)Man produces quite a bit of methane gases as well. Every methane molecule has 20 times the greenhouse potential of CO2 (2). Man actually produces 50-100 million tonnes of methane per year. This is due to the massive increase of two forms of agriculture: Beef and rice. The digestive systems of cows happen to produce a sizeable amount of methane, and rice paddies produce quite a bit as well. (3)To give these combined gases some perspective, imagine that all human gases were measured relative to CO2. Since 1990 alone, we, humanity, have increased our GHG emissions by the equivalent of 6 Gigatons of CO2, a 20% increase. (2)(B) Man contribute to the greenhouse effect both directly, and indirectly. The direct method in which man contributes to the greenhouse effect is through direct emissions of greenhouse gases. The indirect method, though, is limiting the earths ability to curb GHGs presence in our atmosphere. The two most notable effects are deforestation and oceanic pollution. I. DeforestationThe most effective way in which the earth curbs the amount of GHGs produced (specifically, CO2) is through the forests of the earth. The earths forests converts CO2 into O2 and glucose, thus reducing the amount of GHGs present in the atmosphere. Deforestation practices, however, have significantly reduced the earths ability to reduce the presence of CO2. "By most accounts, deforestation in tropical rainforests adds more carbon dioxide to the atmosphere than the sum total of cars and trucks on the world’s roads. According to the World Carfree Network (WCN), cars and trucks account for about 14 percent of global carbon emissions, while most analysts attribute upwards of 15 percent to deforestation. " (4)This results in a much higher quantity of CO2 present in the atmosphere that is a result of mans interference with the environment. II. Pollution of the OceanThe ocean is also a fairly major player in the environment, and GHGs. The ocean naturalyl absorbs GHGs and reduces their concentration. Warming the environment, though, significantly reduces the oceans ability to combat the increase of GHGs. "There’s an important relationship between the atmosphere and our oceans, which is out of balance due to climate change pollution. As oceans warm, they lose their ability to absorb carbon dioxide, causing them to become 'acidified. '" (5). SummaryEven if CO2 initially has very little effect on the enironvment, we can see that the initial effects can quickly spiral out of control and "snowball" into a much more severe effect. Man produces many more GHGs than through simple CO2 emissions. The way in which we cause the greenhouse effect is complex, but almost assuradly the most major cause of modern global warming, as is the scientific census (see Point B, Sub-point 1). Nature and Global Warming/The global warming cycle. Up until about 1950 (where many of my opponents graphs end) the warming period was totally accounted for by natual causes. It wasn't until after then that we began to realize that natual cycles cannot account for modern global warming. Here is a chart illustrating CO2 emissions in PPMs from NASA. As you can see, CO2 emissions are actually much much higher than they have ever been in natural history - 100 PPMs higher than ever. Furthermore, my Point B Subpoint 1 argument shows that the environmental scientific community is in total agreement: Natural cycles simply do not account for modern global warming. The United States Global Change Research Program (which includes the Department of Defense, NASA, National Science Foundation and other government agencies) has said "global warming is unequivocal and primarily human-induced"SummaryThere are countless sources in my R1 argument, and in this argument, that show that the only explanation for the massive upward trend in global average temperatures is that humanity is significantly exacerbating the natural cycle, causing a warming cycle more extreme than any warming cycles in history. I reiterate, Natual Cycles cannot account for modern global warming, and environmental scientists are all in agreement over this point. Via GHG emissions-both directly and indirectly- of all kinds (more than just CO2), man has significantly contributed to the general upward trend of global average temperatures. Sources1. . http://www.theguardian.com...2. . http://environment.nationalgeographic.com...;3. . http://www.ghgonline.org...4. . http://www.scientificamerican.com...;5. . http://www.takepart.com...;