This paper was written as part of the 2010 Alaska Oceans Sciences Bowl high school competition. The conclusions in this report are solely those of the student authors.

Shrinking Ice and the Impact on Polar Bears


Hazel Andrews
Alison DelaRosa
Cindy Lawrence
Nakita Akaran
Martin Mike

Juvenile Gannets

Ignatius Beans Memorial School Complex
PO Box 32105
Mountain Village, Alaska 99632

Arctic sea ice has shrunk to the second-lowest level since record keeping began 30 years ago. Rapid climate change is transforming ecosystems in the northern latitudes such as Alaska and Canada. The extent of Arctic sea ice is now two million square miles below the average for August 26, 2008. According to the data centers recent reports, the ice over the Chukchi Sea is already showing patches of open water where ice usually is. Much of the Beaufort Sea located north of Alaska is open and the Laptev Sea and Eastern Siberian Sea have opened extensively in a short period of time. Researchers now estimate that summer ice in the Arctic is likely to disappear altogether by 2030, but new satellite data suggests sea ice could vanish much sooner then that. Current sea ice reduction is progressing at a very fast rate that appears to have no analogs in the past and that sustained hanged in sea-ice coverage may cause perhaps the largest temperature changes observed on the planet.

polar bears on sea ice

What have Alaska scientists documented?

The average yearly temperatures in Alaska are rising. They rise more during summer than winter. The annual mean temperature in Alaska has been progressing 3.5 degrees Fahrenheit from 1949-2005. The temperatures in Alaska have accumulated more in Alaska over the past 30 years than any other place on earth. Winter temperatures have heated by 5-6 degrees Fahrenheit. It continues to have dramatic effects in an Arctic landscape.

The entire Northern hemisphere has warmed in the last 100 years.

graph of yearly average temperatures

Studies have shown the Arctic ice pack is shrinking and also getting thinner. In the 30 years since scientists started using satellites to indicate the distance of the Arctic ice cap, the size of the ice pack has gotten smaller. However, new research from NASA's IceSAT satellite shows that the ice has been melting faster than anyone predicted. The scientists determined that the ice pack shrank by 57% between 2004 and 2008, and thinning by 2.2 feet.

satellite	images of Arctic sea ice in 2004 and 2008

Alaska storm patterns have changed in severity and are increasing. More storms are emerging in Russia's northern seas, rather than coming from the Pacific Ocean. These storms are most often severe and Alaska's coastline is less protected because of the shrinking ice pack.

Polar Bears

The shrinking sea ice has had an increasing effect on the polar bears. Since the polar bears natural habitat has been changing and being destroyed they are dying out. Though polar bears have swum in open water in the past, they now have to swim much longer distances. Even if researchers spot polar bears swimming in distress, they can't help or try to save them because they would need a tranquilizer, which would cause the bear to drown. In May 2008, Interior Secretary Dirk Kempthorne listed polar bears as threatened under the Endangered Species Act, saying diminishing sea-ice jeopardizes their ability to survive.

On May 14, 2008, polar bears were been put on the endangered species list. This is the first animal brought under the act's protection because of the loss of Arctic sea ice and prognostications that the ice will continue to shrink. According to this article, global warming is not the reason for green house gases. The Center for Biological Diversity, NRDC, and Greenpeace, twice took the Interior Department to court on the ruling in the first place. They are now suing to protect critical habitat and enforce all provisions of the endangered species act. These groups say that the secretary of the interior violated the act by listing polar bear as "threatened" rather than "endangered" and by issuing a special rule exempting green house gas emissions and oil development from regulations under the act.

A listing document stated that because of specific actions such emission from a specific oil plant or oil well couldn't be directed and scientifically amount of warming or ice loss, these radiations could not be controlled by the terms of the ESA. An environmentalist stated that its not like controlling tobacco because of any certain cigarette could be analyzed to have caused a specific cancer.

The reduction of the abiding Arctic sea ice by 14% since the 1970's is causing not only catering and reproducing difficulties, but also flooding and possible cannibalisms among bears. Government scientists have concluded rapid declines of bears in all but the farthest northern range.