July 20, 2013 - North Slope of Alaska
Alaska’s North Slope, which sits almost entirely above the Arctic Circle, is a land of rich resources and rapid change. Home to a half a million migratory caribou, polar bear, grizzly bear, and offering breeding grounds to a host of migratory bird species, the sensitive tundra ecosystem also is home to huge oil reserves, a precious and valuable commodity. In addition, this unique ecosystem lies in an area where the climate is warming as fast as anywhere in the world. It is a delicate, beautiful land that has changed over the last decades, and is predicted to change more rapidly in the future.
The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Terra satellite passed over northern Alaska on July 12, 2013 and captured this clear-sky, summertime view of the North Slope. To the south dark yellow-green taiga covers the mountains of the Brooks Range, which serves as the source of many of the braided rivers that carry snowmelt to the Chukchi Sea (west) and Beaufort Sea (east), which are both marginal seas of the Arctic Ocean. These frigid waters contain free-floating sea ice, even in mid-summer.
The coastal region of the North Slope is treeless tundra, where a layer of permafrost (permanently frozen soil) makes it impossible for trees to grow, and where harsh winds and footing that is wet and boggy in the summer, and thoroughly frozen in the winter, makes it difficult for human habitation, although small villages of people have traditionally thrived in these remote lands, based on a hunting and fishing culture.
The northernmost point in the United States is Point Barrow, with a population of 4,212 reported in the 2010 U.S. Census. It lies at the very tip of the North Slope, at 71°23′20″N latitude 156°28′45″W longitude, and divides the Chukchi Sea from the Beaufort Sea. It also lies on the migration route of the Bowhead whale, an extremely valuable resource to the native hunting and fishing cultures. There is archeological evidence of occupation of this area at least 1,000 years prior to the arrival of any European settlers. In this image, Point Barrow remains covered with snow and ice.