# Climate Change/Printable version

The current, editable version of this book is available in Wikibooks, the open-content textbooks collection, at
https://en.wikibooks.org/wiki/Climate_Change

# Introduction
## Climate

Climate is a broad term, but it always describes a long-term change of a climate system. Often 'climate' is used to mean the long-term mean state of the atmosphere, including temperature, humidity, and wind. In other contexts, 'climate' can include the oceanic state, the cryosphere (snow and sea-ice), the biosphere, and sometimes even the lithosphere (Earth's crust).
Climatology, the science that studies climate, is a young science, with modern climate science only emerging from meteorology, oceanography, and geology in the late 20th Century, it is highly dependent of mathematical models and estimates that rely in a constant gathering of data, improved sensors and historical records (natural or human generated). Of course, people have been interested in the natural world, including movements of air and water, for a very long time. An in general the sciences are still very imprecise at short or very long time frames, even if precision tends to increase over large geographical areas. Meteorologists and atmospheric scientists often say that climate is what you expect; weather is what you get.

## Climate Change

The term global warming was coined by Wallace Broecker, a professor at Columbia University, in reference to the increase in the average temperature of Earth's near-surface air and oceans since the mid-20th century and its projected continuation. The term has fallen in diseuse as it induces error to the general population that can indeed notice that a change is occurring and the climate system is becoming more dynamic but may not perceive the average temperature increase, especially when the extremes are becoming more mediatic, it is easier to show a snow storm, a river overflowing even a hurricane than to visually transmit the sense of temperature especially increase and drought in relatable urban settings and for urbanized audiences.

### Anthropogenic climate change

One early example of a theory for anthropogenic climate change is George P. Marsh's "The Earth as Modified by Human Action," published in 1874. The science in this early effort is far from the level of climate science today, but Marsh does link land use change, including deforestation and irrigation, to changes in the local climate.
Anthropogenic means "human caused," form "anthro-", meaning "human," and "genic," meaning "produced by, origin, cause". The term anthropogenic climate change is used to attribute changes in Earth's climate to activities of humans. In recent times, this has been taken as implying mainly the emission of "greenhouse gases" into the atmosphere, usually by burning fossil fuels.
How can humans change Earth's climate? Even as far back as Arrhenius people have been aware that the composition of the atmosphere affects the climate. Some gases, like carbon dioxide, have molecular structure that allows the absorption of certain wavelengths of light. In the case of "greenhouse gases," that means absorbing infrared radiation. The distinguishing characteristic of a greenhouse gas is that it absorbs infrared radiation better than it does visible radiation; this allows sunlight to penetrate through the gas (the atmosphere) and warm Earth's surface. The Earth then radiates as a blackbody, emitting infrared radiation that is then trapped in the atmosphere. This is the greenhouse effect.
If humans change the composition of the atmosphere, say by burning fossil fuels which release carbon dioxide, then more energy goes into the atmosphere than would have otherwise. More energy leads directly to higher temperature, hence climate change.

### Solar variation

Solar variations are changes in the amount of radiant energy emitted by our Sun. There are periodic components to these variations, the principal one being the 11-year solar cycle (or sunspot cycle), as well as fluctuations which are aperiodic. Solar activity has been measured via satellites during recent decades and through 'proxy' variables in prior times. Climate scientists are interested in understanding what, if any, effect variations in solar activity have on the Earth. Any such mechanism is referred to as "solar forcing".
The variations in total solar irradiance (TSI) remained at or below the threshold of detectability until the satellite era, although the small fraction in ultra-violet wavelengths varies by a few percent. Total solar output is now measured to vary (over the last three 11-year sunspot cycles) by approximately 0.1% or about 1.3 W/m$^2$ peak-to-trough during the 11 year sunspot cycle. The amount of solar radiation received at the outer surface of Earth's atmosphere varied little from an average value of 1366 watts per square meter (W/m$^2$). There are no direct measurements of the longer-term variation and interpretations of proxy measures of variations differ; recent results suggest about 0.1% variation over the last 2000 years, although other sources suggest a 0.2% increase in solar irradiance since 1675. The combination of solar variation and volcanic effects has very likely been the cause of some climate change, for example during the Maunder Minimum. A 2006 study and review of existing literature, published in Nature, determined that there has been no net increase in solar brightness since the mid 1970s, and that changes in solar output within the past 400 years are unlikely to have played a major part in global warming. It should be stressed, the same report cautions that "Apart from solar brightness, more subtle influences on climate from cosmic rays or the Sun's ultraviolet radiation cannot be excluded, say the authors. However, these influences cannot be confirmed, they add, because physical models for such effects are still too poorly developed."

## Nomenclature

Within this wikibook, "Climate Change" is taken to primarily mean "global warming"; which is to say the warming of the Earth seen approximately since the start of the twentieth century. Of course, climate has changed before this time due to natural causes - for example the ice ages.
The United Nations Framework Convention on Climate Change defines climate change as a change of climate which is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and which is in addition to natural climate variability observed over comparable time periods. In this sense climate change is synonymous with global warming.
However the IPCC defines climate change as a statistically significant variation in either the mean state of the climate or in its variability, persisting for an extended period (typically decades or longer). Climate change may be due to natural internal processes or external forcings, or to persistent anthropogenic changes in the composition of the atmosphere or in land use.
Whichever definition is used makes no difference to the changes in climate.

## A Wikibook digression

One contributing author to this wiki book stated that decreased nocturnal cooling may never have been "considered in any debate about global warming." The argument was stated as
   All planets with rotational days unequal to their orbital years absorb their sun's heat during their day and release it at night. In the case of planet Earth, however, not only are we adding to the sun's heat in the daytime; The ever-increasing tendency away from regular day-night cycles of work, play and sleep means that at night, the time when our Earth should be shedding its excess heat, we are still adding to it.
This is a fair argument at first blush, but it does not hold up under scrutiny. While Earth cools much more efficiently at night at the surface, the better cooling does not continue into the upper troposphere very well. That means that most of the energy from the cooling will still end up where it would during the day: either absorbed in the troposphere or emitted to space. Also, the argument seems to imply that increased nocturnal activity by humans makes the cooling less efficient, but it is an extremely small effect. The more efficient cooling at night is due almost entirely to the absence of sunlight. Think of the evolution of the surface temperature as dT = S - F to zeroth order, where S is the solar energy absorbed at the surface and F is the cooling by infrared emission. At nighttime, S = 0, so dT is all due to cooling by emission. During the day, the warming offsets the cooling. We are not adding to the sun's heat, as the contributor states, but just trapping it in the troposphere. That trapping has no diurnal cycle, since there is a negligible diurnal cycle in the concentration of atmospheric constituent gases. Let this be a lesson for the reader: critical thinking should always accompany learning about new topics.

## References

* ^ The text of Marsh's manuscript is publicly available [Gutenberg].
* ↑ "The United Nations Framework Convention on Climate Change". 21 March 1994.

# Science

Climate change has become a "hot button" issue over the past few years, and this has only become more extreme as United States policy on climate change has diverged from much of the rest of the world and the scientific community. However, climate change is first and foremost a scientific topic. In this wikibook, the underlying science of climate change is explored in some detail. The study of climate -- sometimes called climatology or climate science -- is actually a relatively young field, but has roots in all the major branches of science. It is most easily associated with atmospheric science (and its older name, Meteorology) and oceanography. There are also strong connections with the cryosphere (glaciology), the biosphere (biology, ecology), and the lithosphere (especially through the extraction and combustion of fossil fuels). Using basic physical principles, the science of climate change and these connections to other natural sciences will emerge. We will see how computer models, current observation, and studies of ancient climates converge on a singular picture of the near future that includes continued global warming, enhancement of the hydrological cycle, decreasing sea-ice, shrinking glaciers and ice sheets, more acidic ocean water, rising sea level, and more frequent extreme climate events.
Many of the fundamental concepts of climate science are straight out of elementary physics. The equations of motion are the same fundamental equations that govern all classical fluid dynamics, much of energy transfer is based on well-known principles of radiative transfer and nuclear physics and spectrometry, and a lot of observations are based on geological, chemical and biological processes and methods. This is all to say that climate science is a multi-disciplinary field, with diverse (even disparate at times) interests and applications. It is unified only by the end goal: to understand the physical processes governing our natural world. These same physical principles are at work in understanding a changing climate. The main difference is that instead of describing the average or the natural variability of climate, climate change studies try to quantify differences or trends. Past changes and future changes are studied similarly, though sometimes using different tools, as we will see.
When the composition of the atmosphere changes, for example by changing the carbon dioxide concentration, the radiative properties of the atmosphere might also change. In the absence of an atmosphere, Earth would look a lot like a black body radiator; that is to say, the sun would shine on Earth, which would warm to an equilibrium temperature, and then a balance would be struck. That balance (radiative equilibrium) would have Earth radiating as much energy to space as the sun delivers to the surface. Mostly due to the fact that Earth is so small and intercepts so little of the total energy emitted from the sun, that radiative equilibrium temperature is much lower than the sun's temperature. Using Wien's law, we can calculate that temperature and establish that Earth is an infrared emitter.
When there is an atmosphere, like the one on Earth, some of the gases that make up the atmosphere can absorb infrared radiation. That interaction between photons and molecules increases the temperature of the atmosphere, which then emits at a slightly different wavelength. The emission from the atmosphere goes both out to space and downward, back to the ground where it is absorbed by the surface. This process, whereby energy that is emitted from the surface is absorbed by the atmosphere which then emits energy back toward the surface, is called the greenhouse effect, and it is one of the basic feedback processes in the climate system. It increases the surface temperature on Earth from the radiative equilibrium temperature to a much more life-friendly temperature. Global warming, or anthropogenic global warming, is the difference in the global mean temperature in a world with artificially elevated carbon dioxide compared to a reference state (which is usually taken as a time before the Industrial Revolution). In the rest of this part of the book, we investigate the processes involved with climate and climate change, from the sun's influence, to the natural greenhouse effect, to observed changes in the composition of the atmosphere. We will focus on feedbacks and processes that are thought important in both stabilizing and amplifying changes to the global climate.
* Sun's Influence on Earth
* Sun-Earth System
* Distribution of Insolation
* Atmospheric Balance
* Influential Factors
* Present Climate
* Ancient Climate
* Ice Ages
* Climate Modeling
* Other Fields' Research into Climate Change

# Evidence of Change

    See also: w:Global warming
By using various methods of chemistry, geology, and even astronomy, past climate variations are well known. These include the relatively periodic ice ages of the past 2-million years as well as more exotic climates from the Cretaceous and other eras. On such long timescales the main reasons for climate changes must be linked to changes in the sunlight reaching Earth (insolation), major shifts in ocean heat transport, or "external" forcing like volcanism or meteor impacts. More recently, human-induced changes (anthropogenic) are likely a strong climate forcing. Much research has focused on quantifying Earth's climate and its variability over the past 30 years or more. It has been shown that the globally averaged surface temperature is now warmer than it has been for at least 150 years. The trend in surface temperature is remarkably well correlated with a trend in atmospheric carbon dioxide. The current trends are increasing, and the warmest years on record are in the last decade. IPCC
In fact, according to data compiled by NOAA, 2012 ranks 10th warmest since records began in 1880 . The global surface temperature was estimated to be 14.47°C (0.57°C above the 20th Century average of 13.9°C). Amazingly, 2012 was the 36th consecutive year that the yearly global temperature was above average, meaning that more than half the people in the world have never experienced a (globally) average year (median age is 28.4 years, ).
The global average surface temperature continues to rise, but not every year is the warmest year ever. There are variations in the global average surface temperature. These variations are caused by small deviations in the radiative forcing or fluctuations in the rate of heat absorption by the deep ocean. The long-term trend provides a measure of the rate of warming. Putting a linear trend line through the observations of the late 20th Century and early 21st Century provides an estimate of 0.13 °C [0.10 to 0.16 °C] per decade according to the IPCC AR4.
Earth is now absorbing 0.85±0.15 W m$^{-2}$ more energy from the Sun than it is emitting to space. (Hansen et al, 2005, Science vol 308)
The map at right shows an expression of the directly measured temperature change. It shows the temperature anomaly map averaged over the ten years spanning 2000 to 2009 in Kelvin (a centigrade scale, just like Celsius). These anomalies are with respect to the 1961 to 1990 base period. The measurements that go into the HadCRUT3 data set include observations over land from more than 3000 weather stations on at least a monthly basis. For ocean areas, ship-based measurements are used, details are included in published papers (Jones & Moberg 2003 and Rayner set al. 2003).
The time series from the HadCRUT3 data set is also shown at right. While temperature anomalies are fairly uniform in the late 19th Century, the 20th Century shows a strong upward trend. The trend is divided into an early rise from around 1900 to about 1940 followed by a period of little warming (and some cooling) until the 1970s and then a rapid rise from before 1980 until present. These three periods are understood as being driven by different forcing agents. The early 20th Century warming was caused by both increasing carbon dioxide and increasing solar activity. The mid-century cooling and stable period follow rapid industrialization and World War II, and the industrial activity following the war injected an abundance of particles into the atmosphere. These particles, called aerosol, reflect sunlight, which lead to a so-called "global dimming" which decreased the sunlight reaching the surface, thereby reducing the global temperature. The later warming, after 1980 or so is dominated by carbon dioxide, which became a stronger forcing agent than the dimming aerosol as air pollution became more strongly regulated while carbon dioxide continued to rise. (reference)
The analysis of these global patterns of temperature change really brings out the fact that many factors contribute to the global average temperature. A sub-discipline of climatology has emerged that tries to quantify the contributions of various factors to observed climate change; this field is often put into a category called attribution studies. A recent example is Foster & Rahmstorf (2011), that attempts to remove natural factors from the late 20th-early 21st Century climate records. They are able to account for factors such as ENSO, volcanos, and solar variability, leaving the remainder of the trend explained by human-caused factors. Their conclusion is that nearly all of the observed temperature trend is associated with radiative forcing that is ultimately due to rising carbon dioxide concentrations that come from burning fossil fuel.
While the above examples show evidence for the temperature change in the 20th Century, recent climate change is expressed in numerous other climatic indicators. One example is the extent of Arctic sea-ice. As the climate has changed over the past few decades, there has been an unprecedented decline in the area covered by sea-ice in the Arctic Ocean, especially late in the warm season which is also the sea-ice melt season ( Kinnard et al. 2011 ). The most direct way available to track these changes uses satellite observations. The figure at the right shows observed Arctic sea-ice concentration (in percent) for September 1979 and September 2010 from a set of passive microwave observations [NSIDC] These two months show an example of the change in coverage of sea-ice in the Arctic Ocean: September 2010 shows substantially less ice than 1979. September is the end of the melt-season, so these maps are an illustration of the minimum sea-ice coverage in these years. The time series below the maps show the monthly mean sea-ice extent from late 1978 through 2010. Sea-ice extent is the area covered by sea-ice concentration of at least 15%. The annual cycle of sea-ice extent is quite large, oscillating between 15 and 6 million square kilometers in most years. Looking at a particular month shows the long-term trend more obviously. The blue line in the time series plot highlights September sea-ice extent, and it is clear that there is a decline in the September sea-ice minimum. Both the concentration and the extent are an expression of the area covered by ice, but at least as important is the volume of sea-ice. Observations show a pronounced decline in sea-ice volume, similar to the decline in sea-ice extent. The volume is decreasing in the winter months even more strongly than the extent is; this is because the ice that forms in the winter is thin and has less and less volume as the thick ice (that survives through the summer) disappears.
Another indicator of the changing climate is the change in global sea level that has been observed over the last several decades. There are two main effects that are important for the global mean sea-level change. First, as the near-surface temperature increases, heat flows into the ocean's surface waters. As the water temperature rises, the water slightly expands, similar to other materials. This direct temperature effect is called the steric effect on sea-level. The second major factor is the change in the mass balance of the oceans. As the climate has warmed, ice that has been sequestered on land as ice has begun to melt. Much of this melted ice has found its way to the sea, either directly as in the case of calving of ice from Greenland and Antarctic or by making its way to the ocean via streams and rivers. Recent estimates suggest that these two effects combine to account for a long-term trend in sea-level that is more than 3 mm of sea-level rise per year.
Some of the observed evidence that Earth's climate is changing includes:
* Global Temperatures are Rising
* Melting Glaciers
* Sea Levels Rising
* Weather patterns are become more difficult to predict
* Seasonality of weather and temperatures are changing

# Causes

Many believe that $CO_{2}$ and other greenhouse gases (chlorofluorocarbons, methane, sulfur hexafluoride) cause global warming.
* Observed trend in global mean surface temperature
* Observed radiative imbalance at top-of-atmosphere
* Rising atmospheric concentration of $CO_{2}$
* Rising sea level due to thermal expansion of sea-water.

## Criticism

Some people, for a variety of reasons, claim to have found faults with the hypothesis that humans are affecting Earth's climate. While we strive to present any legitimate criticism of the scientific principles where they are presented, this section includes some specific issues that are commonly cited as reasons that humans are not or could not change the climate.
* Lack of scientific consensus
    One of the most common arguments against human induced climate change is a supposed lack of scientific consensus. While there were many skeptical scientists in the past, as the evidence has mounted (especially using satellite-based data), even the most ardent skeptics have come to the determination that humans are changing the climate. One recent study found no instances in the peer-reviewed literature of a study on climate change stating that global warming is either fictitious or purely natural Oreskes, N., Science, 2004, 306(5702), DOI: 10.1126/science.1103618. See also Scientific Consensus.
* The Earth's surface obtains energy from four primary natural sources: space (predominantly solar radiation), the molten core of the Earth, anthropogenic processes that generate excess heat, and radiation from the atmosphere. The second (geothermal heat) is known to be trivially small; the third (direct excess heat) is not as important as increases in the fourth, the energy retention (called the "greenhouse effect"), that is the property of retention heat that could be lost to space due to changes in the atmosphere or surface characteristics, this retention today is mostly due to increases in CO2 levels and receding reflective surfaces like ice or snow. So while indications seems to point to human activities and it is nice to think that changing our energy consumption habits will stop global warming, consideration is needed to account that climate change can be driven by processes that we may have little control over.
* Others, like Bill Ruddiman (U VA) think that we are overdue for an ice age, based on orbital parameters.

# Effects
## Outcomes

* Verified
** More frequent and severe floods and droughts.
** Upper atmosphere (300 km) density reduction.
** Alterations of weather patterns (precipitation, wind and extreme temperatures shifts).
* Expected
** Global mean surface temperature rises.
** Global mean sea surface temperature rises.
** Predicted Surface temperature over land increases more than over ocean.
** Global mean precipitation increases, with a larger increase over the ocean.
** Melting ice is going to make sea levels rise, thus contributing among other things to alterations of precipitation patterns.
** Regional temperature and salinity changes.
** Sea level rises, mostly due to thermal expansion of ocean water.
** Alteration of the plant life growth cycles.
** Higher frequency of extreme weather in general, both cold and hot (averaging on a medium temperature increase), resulting in more high intensity winds (due to low and high pressure zones but with the increased speed and strength) a similar but slower process will also occur in oceanic currents.

## Possible effects on humans

* Increased incidences of respiratory infections, malaria, and other diseases, that are now able to spread (south to north) by animal vectors to new areas.
* Changing growing seasons lead to bad harvests and widespread food shortages, that may also extend to fuel prices when considering bio-fuel production impact.
* Increased droughts cause regional water shortages and increase conflict around water resources.
* Sea levels rise more than expected (>1m), displacing millions of people.
* More frequent flooding leads to coastal destruction and increasing the spread of diseases in developing nations.
* Due to the reduction of the high atmosphere braking effect on low orbital bodies, the use of low orbit for satellites due to the general general increase in the time for the natural degradation leading to burn out will create a higher right to space missions.
* Change of tourism routes/destinations due to negative effects in attractants, like damage to natural monuments and infrastructure will have a detrimental impact in smaller tourism dependent economies.
* A general increase in insurance cost covering the damage caused by weather damage and natural calamities.
* Governmental aid and resources will be increasingly be required to prevent and re-mediate climate change disasters.

## Worst-case scenario outcomes

* Release of methane clathrate from ocean bottom releases enormous amounts of methane to atmosphere, leading to runaway greenhouse effect
* Thawing tundra releases methane trapped in permanently frozen organic matter, leading to enhanced warming
* Increases in precipitation over Greenland, combined with other warming effects there, leads to pools of liquid water that melt into the ice sheet as moulins. Liquid water gets deep into the ice sheet, lubricating and destabilizing it, and huge discharges of ice spill into the north Atlantic.
* Huge discharges of ice spill into the north Atlantic, chilling and freshening the surface water, stabilizing the upper ocean. This shuts down deep convection, and we experience a rapid climate change (not quite so fast as The Day After Tomorrow).

# Mitigation Strategies

In this section, we assume anthropogenic climate change is well underway and examine what individuals and social structures can do to slow or reverse the trend.
It is consensual that at present all strategies to address climate change in a global scale will be extremely infective, not by design but for failure to comply and commit to them, and extremely costly, especially due to the first reason. If measures are not taken simultaneously by all the unbalance will aggravate the impact on those that will attempt to implement them.

## Community contributions to mitigation

This section highlights some current thinking about how communities might deal with a changing climate. These include encouraging people to live closer to where they work, building up (not out), increasing use of public transportation, increasing recycling programs, more efficient use of water resources, more renewable energy sources, and even "green" urban planning.
* Cradle to Cradle: Remaking the way we make things
* Pacala S, Socolow R, 2004: Stabilization Wedges: Solving the Climate Problem for the Next 50 Years with Current Technologies. Science, Vol. 305, No. 5686, pp. 968-972.LINK

## Individual contributions to mitigation

Here we discuss how personal conservation can help to limit greenhouse gas emissions.
* Principles
* In the office - computers, printers, windows, etc.
* In the home - appliances, water use, etc.
* Transport - gasoline, diesel, biodiesel, hybrids, and even bikes/walking.
* Lighting - compact fluorescent bulbs, LEDs, OLEDs
* Heating and Cooling
* Alternative Energy - Roof-mounted solar panels, personal wind turbines, etc.
* Food - Adopt a balanced diet, trade some of the meat, milk, eggs based foods for fish, vegetables, and cereals.
* Sustainable Development

## How societies/countries can reduce emissions

Governments are now aware and intend to take action to reduce greenhouse gas emotions, these are several areas that can contribute to it.
* Carbon Sinks - including sequestration
* Public Transport - efficient urban planning, trains, buses, and shared resources
* Renewable Energy - solar, wind, tidal, geothermal
* Nuclear Power - fission now, fusion later?
* Fossil Fuel Economics - Hubbert's peak and making it a plateau (maybe)
* Natality - Promote family planing and reductions of population.

## See Also

* Energy Efficiency Reference wikibook

# Climate Change in the News

* Article about 2005 Atlantic hurricanes and global warming
* AP article about a study saying Alaskan permafrost may melt, enhancing global warming by releasing greenhouse gases from the soil.
* James Hansen's op-ed in International Herald Tribune, title "It's not too late"
* Lindzen's April '06 op-ed in Wall Street Journal
* Lindzen's July '06 op-ed in Wall Street Journal, trying to attack An Inconvenient Truth by Al Gore
* Oreskes' response to Lindzen and others, from July '06, published in Los Angeles Times
* Peter Doran responds to global warming deniers in the New York Times in July '06
* World Emissions of Carbon Dioxide Outpace Worst-Case Scenario
* Carbon Emissions Hit 20-Year Low
* Pentagon Unveils Plan For Military's Response To Climate Change
* Study: Past Climate Change Was Caused by Ocean, Not Just the Atmosphere
* Climate Ark - continuous updates
* Google News - search for climate change
* UK climate meeting calls for action - Nature.com, 3rd Feb 2005, strap line: "Researchers discuss 'dangerous' change as global-warming fears grow."
* Landfall Nears For Strongest Hurricane In Recorded History
* El Niño Is Going to Starve a Lot of Fish
* Carbon Pollution Touched 800,000 Year Record in 2016, WMO Says - slashdot.org, October 30, 2017.
* Tourism Representative Blames Scientists for Downturn in Great Barrier Reef Visits - SoylentNews, January 14, 2018.
* 2017 was among the warmest years on record, according to new data released by NASA and the National Oceanic Atmospheric Administration. - slashdot.org, January 18, 2018.
* Global Warming Predictions May Now Be a Lot Less Uncertain - slashdot.org, January 18, 2018.
* Earth's Carbon Dioxide Levels Reach Highest Point In 800,000 Years - slashdot.org, May 06, 2018.
* Invisible Scum on Sea Cuts CO2 Exchange With Air 'By Up To 50%' - slashdot.org, May 28, 2018.
* Coastal Megacity Karachi Is Running Out of Water - slashdot.org, May 28, 2018.

# Further Reading
## Non-technical works

* Broecker, Wallace S. and Robert Kunzig: Fixing Climate: What Past Climate Changes Reveal About the Current Threat--and How to Counter It. Hill and Wang, 272 pp. ISBN-10: 0809045028, ISBN-13: 978-0809045020
* Fagan, Brian: The Great Warming: Climate Change and the Rise and Fall of Civilizations. Bloomsbury Press, 304 pp. ISBN-10: 159691601X, ISBN-13: 978-1596916012.
* Flannery, Tim: The Weather Makers: How Man Is Changing the Climate and What It Means for Life on Earth. Grove Press, 400 pp. ISBN-10: 0802142923, ISBN-13: 978-0802142924.
* Kolbert, Elizabeth, 2006: Field Notes from a Catastrophe: Man, Nature, and Climate Change. New York, NY, Bloomsbury. ISBN: (978-)1-59691-125-3
* McDonough, William and Michael Braungart, 2002: Cradle to Cradle: Remaking the way we make things. North Point Press.
* Hillman, Mayer, Tina Fawcett and Sudhir Chella Rajan, 2007: The Suicidal Planet: How to Prevent Global Climate Change. New York, NY, St. Martin's Press.

## Textbooks

* Burroughs, William James, 2001, Climate Change: A multidisciplinary approach, Cambridge Univ. Press, 320 pp. ISBN: 0521567718.
* Hartmann, D. Global Physical Climatology
* Peixoto & Oort, Physics of Climate
* Holton, J. Introduction to Dynamic Meteorology, 4th Ed.
* Archie Duncanson. "Ecology Begins at Home" ISBN 190399845X. Free downloadable version is available. Contains many methods to reduce your footprint on planet Earth.
* Sophie Uliano. "Gorgeously Green: 8 Simple Steps to an Earth-Friendly Life" ISBN 0061575569. Women way to solve everyday problems with reducing impact on planet and improving heath.
* Anita Evangelista. "How to Live Without Electricity and Like It". ISBN 0966693213. Provides great insights into low-tech solutions for everyday problems.
* Giles Slade. "Made to Break: Technology and Obsolescence in America" ISBN 0674022033. Gives overview of history of technologies embedded in everyday life of modern society and wasteful culture.
* Richard Heinberg. "The Party's Over: Oil, War and the Fate of Industrial Societies". ISBN 0865714827. Interesting philosophical outlook on history of technological civilization and it's possible fate.
* Human Footprint video by National Geographic Channel
* Elizabeth Royte. "Bottlemania: How Water Went on Sale And Why We Bought It". ISBN 1-59691-371-1. History and problems of bottled water with comprehensive review of issues with tap water and additional filters.
* "Food, Inc. How Industrial Food Is Making Us Sicker, Fatter, and Poorer — And What You Can Do About It". ISBN 978-1-58648-694-5. Great insight into modern industrial food production system.

## Scientific Literature

* Hansen et al., 2005. Science 308[3]
* Hegerl, Gabriele C., Thomas J. Crowley, William T. Hyde and David J. Frame, 2006: Climate sensitivity constrained by temperature reconstructions over the past seven centuries. Nature 440(7087), pp. 1029-1032. doi:10.1038/nature04679
* Oreskes, Naomi, 2004. Science 306(5702), DOI: 10.1126/science.1103618.
* Pacala S, Socolow R, 2004: Stabilization Wedges: Solving the Climate Problem for the Next 50 Years with Current Technologies. Science 305(5686), pp. 968-972. LINK

# FAQs
## Kyoto Protocol and the United States
### What is the Kyoto Protocol?

The most basic objective of the Kyoto Protocol is to reduce harmful greenhouse gas emissions prior to the levels of 1990. This protocol and its agreements are a legally binding contract for developed countries to reduce six of the leading greenhouse gases: carbon dioxide, methane, nitrous oxide, sulphur hexafluoride, Perfluorocarbons (PFCs), and Hydrofluorocarbons (HFCs)/Chlorofluorocarbons (CFCs). These gases are naturally occurring, except for the last four: SF6, PFCs, HFCs, and CFCs. These gases have a direct impact to Global Warming.

### What is the greenhouse effect?

Greenhouse gases contribute to global warming, which is caused by the greenhouse effect. The greenhouse effect can be demonstrated in this way: suppose you are driving in a car on a hot summer day. The sun's rays shine down into your car through the windows. However, the heat cannot get out of the car because the windows reflect the heat trying to get out back towards the interior of the car. This causes the car to continue to heat up until the thing blocking the heat from getting out is removed or a cooling element of some type is activated in the car.
In the subject of global warming, the greenhouse gases are the "windows" and the Earth is the "car." The sun's rays are somewhat deflected or absorbed through their travel through space and the atmosphere, but most of the energy still reaches the Earth's surface. This energy is reflected back toward space by the Earth, but because of the greenhouse gases it cannot go back into space. Therefore, the entire Earth warms up.
The global temperature has only risen a few degrees since the start of the Industrial Revolution. However, one must remember that we are talking about a global temperature increase, not just in one relatively small location. One would expect the temperature in one location to be varied, but the forces required to raise the average temperature on the entire planet would have to be immensely strong.

### Why are greenhouse gases detrimental to the environment?

Granted, greenhouse gases (GHG) occur naturally in the environment, but since the Industrial Revolution, humans have intensified this process by emitting more GHG into the atmosphere than our environment can handle. The main contenders are the automobile makers, industries such as coal (fossil fuel) burning power plants, and even landfills which release large amounts of hazardous methane (from decomposition). Some parties assert that this actually helps plant life to grow, on account of the fact that plants absorb carbon dioxide as a part of their photosynthesis. While this may be true, when the plant decays, the stored carbon is released back into the air. Scientists are afraid that if the dumping of greenhouse gases continues at the present rate, plant life may not be able to keep up.

### Where does the US stand on the Kyoto Protocol?
## Further Reading

To read the Articles listed under the Kyoto Protocol, please visit the United Nations Framework Convention on Climate Change:
For more general information about Kyoto Protocol, visit Wikipedia's page:
To better understand Global Warming, check out the EPA's site:

# External Links
## External Links

* National Energy Foundation Home
* CO$_2$ calculator
* MIT's Global Change website
* Global Warming
* A distributed computing project to predict climate change
* Pew Center on Global Climate Change - news, explanation, policy, and activism
* The Climate Ark is a Climate Change Portal and Search Engine
* Introduction to climate change... good for younger audience too.
* US Global Change Research Program
* Canada's introduction, including Kyoto Protocol information
* Local effects of climate change
* RealClimate
* Intergovernmental Panel on Climate Change