Global Warming

The Arctic is a highly sensitive region, and it's being profoundly affected by the changing climate. Many scientists believe that global warming is the cause. Average temperatures in the Arctic region are rising twice as fast as they are elsewhere in the world. Satellite photos have shown that the Artic region is shrinking in size since the 1970's (Global Warming: The Silent Threat). In the last two decades, temperatures have been rising in the Arctic at a rate 20 times faster than the warming that occurred over the previous century, and the thickness of the ice sheet has decreased by about half (down from 15 feet in the 1980s to 8 feet in 2003). Springs are coming earlier, and fall is arriving later, which combined with higher summer temperatures year after year contribute to the gradual shrinking of the permanent ice sheet (Cox 14).

Climate scientists since the mid 1970's have predicted that warming would come first and strongest in the Arctic after 1995. The change has been increasingly evident, both to scientists and to indigenous people. In Alaska and western Canada, winter temperatures have gone up as much as 7 degrees F over the past 50 years. Since the mid 1970's, the floating Arctic ice pack has lost an area the size of Texas and Arizona combined. With a shorter season of sea ice, fall storms batter Alaska's Arctic coast as never before, causing erosion that threatens communities (Wohlforth 9). Arctic ice is getting thinner, melting and rupturing. For example, the largest single block of ice in the Arctic, the Ward Hunt Ice Shelf, had been around for 3,000 years before it started cracking in 2000. Within two years it had split all the way through and is now breaking into pieces (Global Warming: The Silent Threat).

How can a few degrees change the world? A warming of 1.1Ñ"F over the past century and a further 2.5-10.4Ñ"F over the 21st century, as projected by IPCC, may appear minor compared to short-term weather changes from night to day and winter to summer. However, in global climate terms, a warming at this rate would be much larger and faster than any of the climatic changes over the past 10,000 years. Global temperatures during the last ice age (about 20,000 years ago) was 9oF cooler than today, but that was enough to allow massive ice sheets to reach as far south as the Great Lakes and New York City (Armageddon to Come).

Rising temperatures are already affecting Alaska, where the spruce bark beetle is breeding faster in the warmer weather. These pests now sneak in an extra generation each year. From 1993 to 2003, they chewed up 3.4 million acres of Alaskan forest. The effects of global warming on the north are not limited to the Arctic. Higher temperatures are already affecting people, wildlife and landscapes across Alaska. Melting glaciers and land-based ice sheets also contribute to rising sea levels, threatening low-lying areas around the globe with beach erosion, coastal flooding, and contamination of freshwater supplies. At particular risk are island nations like the Maldives; over half of that nation's populated islands lie less than 6 feet above sea level. Even major cities like Shanghai and Lagos would face similar problems, as they also lie just six feet above present water levels (Armageddon to Come). In Bangladesh, sea level will be about 40 cm higher than today by the 2080s, and this is estimated to increase the annual number of people flooded from 13 million to 94 million. 60% of this increase will occur in southern Asia, and 20% will occur in South East Asia (Sea Label Rise & Bangladesh).

Rising seas would severely impact the United States as well. Scientists project as much as a 3-foot sea-level rise by 2100. According to a 2001 U.S. Environmental Protection Agency study, this increase would inundate some 22,400 square miles of land along the Atlantic and Gulf coasts of the United States, primarily in Louisiana, Texas, Florida, and North Carolina (Brokaw).

A warmer Arctic will also affect weather patterns and thus food production around the world. Wheat farming in Kansas, for example, would be profoundly affected by the loss of ice cover in the Arctic. According to a NASA Goddard Institute of Space Studies computer models, Kansas would be 4 degrees warmer in the winter without Arctic ice, which normally creates cold air masses that frequently slide southward into the United States. Warmer winters are bad news for wheat farmers, who need freezing temperatures to grow winter wheat. And in summer, warmer days would rob Kansas soil of 10 percent of its moisture, drying out valuable cropland (Armageddon to Come).

Melting of polar ice and land-based glaciers is expected to contribute to the 3.5 inch to three feet of sea level rise, which is projected the 21st century. Shrinking ice caps may also cause changes in ocean circulation and even storm tracks. The polar ice cap as a whole is shrinking. Images from NASA satellites show that the area of permanent ice cover is contracting at a rate of 9 percent each decade. If this trend continues, summers in the Arctic could become ice-free by the end of the 21st century (Is the Artic Melting?).

The melting of once-permanent ice is already affecting native people, wildlife and plants. When the Ward Hunt Ice Shelf splintered, the rare freshwater lake it enclosed, along with its unique ecosystem, drained into the ocean. Polar bears, whales, walrus and seals began changing their feeding and migration patterns, making it harder for native people to hunt. Polar bears are endangered species and super computers are predicting that they would become extinct by the end of the 21st century or even sooner (Brokaw). Along Arctic coastlines, entire villages will be uprooted because they are in danger of being swamped. The native people of the Arctic view global warming as a threat to their cultural identity and their survival (Is the Artic Melting?).

The Arctic ice melt will have effects beyond the polar region. The contraction of the Arctic ice cap is accelerating global warming. Snow and ice usually form a protective, cooling layer over the Arctic. When that covering melts, the earth

...