"We'll continue to get a slow, sunny, erratic warming through the next few centuries—which is far better than the alternative of another harsh, cloudy, unstable Little Ice Age." —Dennis T. Avery, senior fellow at the Heartland Institute, an organization that promotes free market solutions to social and economic problems.
Dennis T. Avery, "Our Moderate Climate Crisis," Heartland Perspectives, October 18, 2007.
In the United States, according to the IPCC report, temperatures in northern states will warm primarily in the winters, while southwestern states will experience higher summer temperatures and much less rain. IPCC climate models suggest that by 2100 the eastern, western, and southern edges of the country might warm between 3.6 and 5.4 degrees Fahrenheit (2 and 3 degrees Celsius), and the northern regions by 12.6 degrees Fahrenheit (7 degrees Celsius). Alaska may experience the most warming— as much as 18 degrees Fahrenheit (10 degrees Celsius). Temperature increases in these ranges will almost certainly produce major climate and lifestyle changes for Americans.
The Earth's climate is highly complex, however, and experts say it is possible that the climate could change even more rapidly
than scientists now predict. One factor that cannot be figured into the climate models used by IPCC scientists is known as climate feedbacks—changes in climate that occur in response to rising temperatures. These feedbacks can either increase or decrease the effects of global warming.
One example of positive feedback that could produce additional warming involves melting Arctic sea ice. This melting could, in turn, add to the Earth's warming because the loss of large sections of highly reflective ice would mean that less sunlight is reflected back into space and more of this energy is absorbed by the oceans. Similarly, if higher temperatures produce more drought and more forest fires, the decrease in carbon-absorbing greenery and the burning of these organic matters is expected to add carbon to the atmosphere and increase global warming.
An even more worrisome positive feedback is the increased rate of decay of organic matter in soils—a process that increases atmospheric carbon levels, enhancing the greenhouse effect.
This phenomenon is expected to be especially widespread in areas in the Arctic region, such as Alaska and Greenland, where higher temperatures could melt permafrost—long-frozen land areas that store massive amounts of carbon from decayed vegetation that grew during prehistoric warm periods. Walter Oechel, a scientist studying this problem, is concerned that this feedback could tip the Earth into an uncontrollable warming cycle. He explains: "Humans [now] are putting about 6 billion or 7 billion metric tons of carbon in the atmosphere a year, and we are standing on 200 billion tons here [in Alaska]. If any significant portion came out, that dwarfs the current human injection into the atmosphere. And once that runaway release occurred, there'd be no way to stop it."17
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Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.