The Arctic is one of two polar regions in the world.
Centerpiece is the Arctic Ocean which is surrounded by continental land masses and islands.
The Arctic Circle, an imaginary line at latitude 66 degrees, 30 minutes North, defines the southern boundary of the Arctic region.
Other definitions of the Arctic include the area north of the treeline and where the average daily summer temperature does not rise above 10 degrees Celsius.
The Arctic Ocean
Smallest of the world’s oceans and the most landlocked of all oceans.
Covered by a perennial drifting polar icepack that averages about 3 meters in thickness. The icepack is surrounded by open seas during the summer, but more than doubles in size during the winter and extends to the encircling landmasses.
Ocean floor is about 50% continental shelf.
Influenced by rivers – receiving 11% of world river runoff.
Interactions of arctic ocean currents with the atmosphere influence climate patterns throughout the Northern Hemisphere.
Characteristics of the Arctic
Extreme seasonal cycles of photoperiod and temperature
Winter, much of the land in the far north is under snow and ice. However, a large portion of the Arctic is comprised of forested and tundra regions where numerous plants, shrubs and trees grow.
Summers begin around mid-July and end late-August. Winters have little snow or rain falls, the sun never rises and temperatures may go down to 40 below Celsius.
Land & Marine Ecosystems
Land is generally continuous permafrost, preventing water from percolating into the ground – creating numerous lakes and marshes.
Major land ecosystem is tundra vegetation.
Much of the marine ecosystem is covered in pack ice.
Much of the marine life depends on presence of sea ice for food.
Both ecosystems have plants and animals that have adapted to survive the extreme environments.
People and Cultures
People have lived in the Arctic for millennia - Eskimo (comprised of the Inuit, Inupiat, Yupik and several other groups), who range from Alaska to Canada and Greenland, the Saami (previously called the Lapps) of Scandinavia, the Nenets of Northwest Russia, the Sakha (Yakut) of Russia and the Chukchi of Siberia.
Many remain dependent on subsistence species like caribou and walrus – vulnerable species to changing environmental conditions.
Several large cities inside the Arctic Circle, including Barrow, Alaska; Tromso, Norway; and Muramansk and Salekhaard in Russia.
Arctic contains natural resources significant to the world economy – oil, gas, diamonds, coal, gold, zinc, and other minerals.
Why Study the Arctic?
Least studied and understood of the world’s regions.
Interacts in complex and significant ways with global climate systems.
Contains historical information about past climates – a window to the present.
Models suggest climate change will be detected and amplified in the polar regions first.
One of the best places to detect the effects of human activities on climate and the environment.