In March 1989, the Exxon Valdez spilled 10.8 million gallons of Alaskan crude oil into Prince William Sound, killing thousands of birds and fish, and significantly affecting marine mammals and other wildlife. The accident and its aftermath became one of the most publicized environmental disasters in history.
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a. Bering Glacier Changes, 1900-1992 b. Prince William Sound Region c. Beetle Infestation (acres) | |
What has received far less publicity however, is the environmental effects on the region of the vast majority of oil that is not spilled but is delivered to customers to be burned in car engines, power plants and building heating systems. Oil and gas, along with coal, are the major contributors to global climate change.
Prince William Sound lies on the edge of a vast warming area that stretches from western Canada to the Bering Strait. As a result, some of the world's most dramatic and best documented impacts of climate change can be found nearby.
Although the terminal lobe of the Bering Glacier, located just to the east of Prince William Sound, is slightly smaller than the nearby Malaspina Glacier, the total complex, including the Bagley Icefield, covers 5174 square kilometers and is 191 kilometers long, making it both the largest and longest glacier in North America outside of Greenland. The Bering Glacier, originating in Canada's Yukon Territory, is one of the most active glaciers in the world, sometimes surging forward hundreds of meters in a few months, and then retreating almost as rapidly, calving off huge icebergs and forming large meltwater lakes in the process.
The Bering Glacier has retreated dramatically since the beginning of the century (see illustration). Only a narrow and rapidly eroding sandbar prevents enormous calved icebergs from escaping into the Gulf of Alaska and threatening shipping and oil tankers.
More than 25 million trees have been killed and over 1.2 million acres of forest infested by the worst spruce bark beetle outbreak in Alaskan history. Spreading rapidly on the Kenai Peninsula, the outbreak has now reached Anchorage. The vast numbers of dead and dying trees have also created a major forest fire hazard.
Although bark beetles are indigenous to the Alaskan boreal forest, the unprecedented size of this outbreak has been linked to climate change by U.S. Forest Service scientists. Climate change has increased forest water stress, improved conditions for beetle brood development, reduced winter mortality, created a larger dispersal period, and allowed beetles to reach sexual maturity in one year rather than two.