The polar regions at each end of the earth’s axis are alike in some ways and very different in others. The tilt of the axis brings extremely cold winter darkness as well as long summer daylight hours to both the North and the South Poles. Both are permanently covered with ice and snow, but the surrounding oceans teem with many varieties of marine life. There is no landmass around the North Pole, only frozen water. The Arctic Ocean is separated from other oceans by the landmasses of Asia and North America, which limit currents and marine animal migration. The North Polar icecap stays about the same size all year long, though its fringes melt during the brief summer, breaking off as icebergs. The region is blanketed by new snow every year and is influenced by warm and cold winds from nearby Canada, Greenland, and Siberia. Unlike the South Polar region, the Arctic Polar region, the Arctic has a permanent native human population living around its edges. Called the Inuit, they have adapted over many centuries to its extreme climatic conditions.

 

 

Fast facts

Area
Arctic Ocean: 12,260,000 sq km (4,734,000 sq miles)
Antarctica: 13,209,000 sq km (5,100,400 sq miles)

Coldest recorded temperatures
Arctic: -67,7°C (-89.9°F)
Antarctic: -89°C (-128.6°F)

Normal high temperatures
Arctic: 20°C (68°F)
Antarctic: -15°C (5°F)

Largest resident land animal
Arctic: Polar bear-roughly 2 m (7 feet) from nose to tail
Antarctic: Springrail-12 mm (0.5 inches) long

 

Bearing the cold
About 20,000 polar bears live on the Arctic ice, hunting for seals, walrus and fish. Their webbed toes help them swim well, and hair on the soles of their feet keeps them warm. Polar bears grow dense, waterproof undercoats; their outer coats have hollow guard hairs that trap any warm air.

 

Arctic seals
Born and bred on the ice pack, seals can regulate their blood flow and store oxygen supplies their bodies while swimming in the frigid water. Baby seals grow very fast. The hooded seal pups gain about 7 kg (15 lb.) a day during the four to five days that they are nursing.

 

People in the Arctic

Driving on ice
For centuries, Arctic travellers have used dogsleds for transportation. Since the 1950s, snowmobiles have been taking over. Some people, though, continue to prefer dogs. They are cheaper to buy and don’t break down easily. And as one Inuit pointed out, in case of emergency «you can’t eat your snowmobile».

 

Arctic pollution
Oil spills from tankers have killed wildlife and disrupted food chains. Global warming softens fringe ice, allowing more icebreakers and submarines into Arctic waters; their fuel leaks are toxic.

 

Walruses
Walruses are social animals that live in groups of up to 100 amid the ice along the Arctic shores. The massive adults can weigh 0.9 t (1 tn.) or more. Both males and females grow tusks, which they use to hoist themselves up onto land. Rooting about on the seafloor with their snouts, walruses suck clams out of their shells, eating thousands of clams per day. To attract mates, males bellow song sequences that carry for a mile or more underwater.