Climate Change In Alaska

Curved patterns of Muldrow Glacier against mountainous backdrop by Kim Heacox.

Scientists predicted that man-made climate change would be felt first and very intensely in Alaska. They were right. In Alaska, winter temperatures have increased as much as 5-7° Fahrenheit (F) over the last 50 years. Over the next 100 years, under a moderate emissions scenario, annual average temperatures are projected to rise 5-9°F over land and up to 13°F over oceans.

Alaska is a harbinger of things to come, a visual symbol of the significant and costly negative impacts climate change will have on our nation and our planet. We are, indeed, the rapidly melting tip of the iceberg.

Melting glaciers and global sea level rise
Warming temperatures are a major contributor to Alaska’s particularly fast rate of glacial retreat. McCall Glacier in the Brooks Range has thinned 33 feet in the last four decades. A 2002 study of 67 Alaskan glaciers found that most are melting at a rapid rate, shrinking by an average of more than a foot each year from the 1950s to the 1990s, and some nearly 6 feet a year from the mid-1990s to 2001.

Global average sea level rose by about eight centimeters (three inches) in the past 20 years, and is on the increase. This rise is due primarily to thermal expansion, brought on by ocean warming and melting of land-based ice that increases the total amount of ocean water. Global average sea level is predicted to rise between four inches and three feet during this century, with the rate of rise accelerating over time.
Thawing permafrost
Permafrost on the Alaskan Arctic coastal plain and arctic foothills warmed approximately 3°C since the late 1980s and 2-3°C near Prudhoe Bay since the mid-1980s. Discontinuous permafrost around Alaska is warming and thawing and extensive areas of subsidence are occurring as a result of climate change. Warming permafrost is undermining the physical foundation of Alaska’s boreal forests, roads, utility infrastructure, pipelines and buildings. It also affects the availability of groundwater and surface water and contributes to increased erosion along Alaska coasts and rivers.
Faster warming
Alaska and the Arctic are warming faster than any other part of the globe, with temperatures increasing twice as quickly as those in the rest of the world over the last 100 years.
Infrastructure damage
Rising temperatures are already thawing out Alaska. At present, four Alaska villages are relocating. The Army Corps of Engineers estimates that relocating just one of these villages would cost between $100 million and $400 million. Several other threatened villages will require extensive mitigation to protect them from environmental changes. The combined costs of these and other damages to infrastructure may turn out to be quite substantial.
Threats to our forests
Forest fires and insect infestations are projected to continue to increase in frequency and intensity as the warming climate increases conditions conducive to their proliferation. Current trends are already reflecting these expectations. In 2004, Alaska witnessed 600 fires and lost a record-setting 5 million acres of its forests. During the 1990s, the Kenai Peninsula experienced the world’s largest outbreak of spruce bark beetles, resulting in the loss of millions of healthy trees and increasing the risk of forest fire.
Cultural impacts
Alaska’s cultures are also at risk. Subsistence ways of life are being impacted as the migration patterns of whales, walrus, caribou, moose, and other animals change. Hunting and fishing is becoming more dangerous with changing sea and river ice. Areas traditionally used for berry-picking and plant gathering are no longer dependable. The Iditarod sled dog race has had to re-start outside of Anchorage several times due to lack of snow.
Public health threats
Health concerns caused by climate change include increased flooding and the arrival of new animal species that could bring diseases such as the West Nile Virus. Climate change is also affecting public health around Alaska. Water sources in many rural villages in Alaska are threatened as the permafrost warms, storm severity increases, and infrastructure is damaged. Increased rainstorms and sea level rise can contaminate groundwater or surface water supply. Wastewater collection, treatment and disposal systems can be damaged by storm surges and permafrost thawing. As traditional foods become scarce, diets will change. And, as temperatures warm, Alaskans will be susceptible to more infectious diseases.
Threatened Landscapes, Wildlife and Fisheries

Boreal forests are advancing northward. Displacing tundra, and to higher elevations. Boreal forests are expected to expand north at a rate of about 100-150 km per degree centigrade temperature increase. Southern forests in Alaska are being lost to drying, fire, and insect infestation. Polar bears are unlikely to survive if there is an almost complete loss of summer sea-ice cover, which may occur by the end of the century. Warming streams and increased siltation from melting glaciers are affecting salmon populations. Migratory bird ranges are shifting and migration times are changing.