Global Warming


Carbon Cycle Photosynthesis plays a crucial role in the carbon cycle. Carbon continuously circulates in the earth’s ecosystem. In the atmosphere, it exists as colorless, odorless carbon dioxide gas, which is used by plants in the process of photosynthesis. Animals acquire the carbon stored in plant tissue when they eat and exhale carbon dioxide as a by-product of metabolism. Although some carbon is removed from circulation temporarily as coal, petroleum, fossil fuels, gas, and limestone deposits, cellular respiration and photosynthesis balance to keep the amount of atmospheric carbon relatively stable. Industrialization, however, has contributed additional carbon dioxide to the environment.

Global Warming, increase in the average temperature of the atmosphere, oceans, and landmasses of Earth. The planet has warmed (and cooled) many times during the 4.65 billion years of its history. At present Earth appears to be facing a rapid warming, which most scientists believe results, at least in part, from human activities. The chief cause of this warming is thought to be the burning of fossil fuels, such as coal, oil, and natural gas, which releases into the atmosphere carbon dioxide and other substances known as greenhouse gases. As the atmosphere becomes richer in these gases, it becomes a better insulator, retaining more of the heat provided to the planet by the Sun.

The average surface temperature of Earth is about 15°C (59°F). Over the last century, this average has risen by about 0.6 Celsius degree (1 Fahrenheit degree). Scientists predict further warming of 1.4 to 5.8 Celsius degrees (2.5 to 10.4 Fahrenheit degrees) by the year 2100. This temperature rise is expected to melt polar ice caps and glaciers as well as warm the oceans, all of which will expand ocean volume and raise sea level by an estimated 9 to 100 cm (4 to 40 in), flooding some coastal regions and even entire islands. Some regions in warmer climates will receive more rainfall than before, but soils will dry out faster between storms. This soil desiccation may damage food crops, disrupting food supplies in some parts of the world. Plant and animal species will shift their ranges toward the poles or to higher elevations seeking cooler temperatures, and species that cannot do so may become extinct. The potential consequences of global warming are so great that many of the world's leading scientists have called for international cooperation and immediate action to counteract the problem.

References

Christianson, Gale E. Greenhouse: The 200-Year Story of Global Warming. Walker, 1999.
A historical look at global warming. For general readers.

Harvey, Danny. Climate and Global Environmental Change. Prentice Hall, 2000.
A textbook explanation of climate and of natural and human-induced climate changes.

Houghton, John. Global Warming: The Complete Briefing. 3rd ed. Cambridge University Press, 2004.
A comprehensive guide to the science and politics of global warming.

McKibben, Bill. The End of Nature.
A popular classic that outlines the greenhouse effect and the actions we can take to combat it.

Moore, Thomas Gale. Climate of Fear: Why We Shouldn't Worry about Global Warming. Cato Institute, 1998.
Interprets global warming as a myth and hysteria rather than a legitimate environmental concern. For young adult and adult readers who wish to examine both sides of the global warming issue.

Philander, S. George. Is the Temperature Rising? The Uncertain Science of Global Warming. Princeton University Press, 1998.
Takes the middle ground between the extremes of the global warming controversy.

Schneider, Stephen H. Laboratory Earth: The Planetary Gamble We Can't Afford to Lose. Basic Books, 1997, 1998.
A leading authority on climate change discusses the history of global warming.

Cited "Global Warming," Microsoft® Encarta® Online Encyclopedia 2004
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