Alaska North Slope
The North Slope is a region in the U.S. state of Alaska, with an area of 230,500 km ². Large parts of the region are located in the North Slope Borough. It is limited by the northern slopes of the Brooks Range in the south and the Chukchi Sea and Beaufort Sea, the, marginal seas of the Arctic Ocean, to the north.
The National Petroleum Reserve - Alaska ( NPR -A) with the oil field at Prudhoe Bay is located in the region. The oil produced is transported to the trans-Alaska pipeline to the south. The Arctic National Wildlife Refuge, the northernmost protected area of the United States, located in the coastal plain of the North Slope. The Dalton Highway is the only road link to the region.
Only the uppermost layers of the tundra soil of the North Slope thaw in summer. In this permafrost the rain and melt water flows into wide, flat streams to the sea or forms large ponds and lakes. North of the Arctic Circle in Alaska decreases the tree line at sea level, the North Slope is thus free of trees. On the slopes of the Brooks Range Tundra swans nest among others, arctic terns, skuas Falk, plush head ducks and snowy owls. The two largest caribou herd in Alaska, the " Western Arctic " with up to 400,000 animals and the " Porcupine " with about 160,000 animals, wander through the North Slope.
In the North Slope polar climate. The pent-up of the Brooks Range Arctic air masses and caused by the shallow angle of incidence small annual energy irradiation can the average temperature in July is not above 10 ° C rise. The long sunshine periods in summer are enough, however, to give rise to an ice-free belt on the Arctic coast. The rainfall is about 120 mm per year compared to the desert regions.