The Arctic sits on top of the world and is the area lying above 66 1/2 degrees North Latitude that includes the Arctic Ocean and lies between North America and Russia. In contradiction to Antarctica, which is a large continent covered with a sheet of ice, the Arctic is an ocean covered with a layer of ice.

The word Arctic originates from the Greek word arktos which means bear. The connection between the Arctic and a bear is that the bear constellation, Ursa Major, is located in the northern sky near the north pole of heavens.

The Arctic Ocean covers four million square miles, is two miles deep and is covered with a layer of ice which is 8 to 12 feet thick. You can compare it with a bucket of water with a thin layer of dust on the surface - the bucket representing the Arctic Ocean, the layer of dust the ice.

Four major rivers pour into the Arctic Ocean - the Mackenzie river in Canada , the Lena, Ob and Yenisey in Russia. Many minor rivers in North America, Europe and Asia also pour into the Arctic Ocean. The flow from these continental rivers flowing into the Arctic basin, incorporate 10% of the worlds river discharge, an amount equivalent to six times that of the Mississippi River.

Throughout the year, most of the Arctic Ocean is covered by a relatively thin layer of ice (12 feet deep). In some areas, warm water upwells to the surface, creating ice-free patches. These patches are called polynias and attracts the marine life - seals gather there to harvest fish, and polar bears gather to harvest seals.

The ice covering -- or as it is called "the pack ice" of the Arctic Ocean is far from static. It is being shifted around all the time by the wind and ocean current drifting  3 to 9 miles (5-15 km) per day.

All this movement causes the pack ice to break into HUGE plates. Sometimes these plates CRASH together -- as you can imagine with great force -- creating what is called "Pressure Ridges". At 50 ft (15 km) they can be as tall as a building and last for miles and miles on end. Under the water the ridges are three to four times the height they are above.

The Arctic’s influence on the Global System
The Arctic has a profound impact on the world’s ocean and weather systems. Water flowing out of the Arctic Ocean through the narrow Fram Straight in the Greenland-Iceland-Norwegian sea in the controlling mechanism for the world’s ocean currents which, in turn, influence the Earth’s weather systems. Cold, dry air over the arctic interacts with warm, moist air from equatorial regions and this interaction is responsible for the majority of weather patterns in the Northern Hemisphere.

Impact of the World on the Arctic
The Arctic is a barometer for the health of the world. Long considered to be a pure and pristine region, beyond the reach of industrial activities. However, the Arctic is the recipient of contaminants transported from as far away as the mid-latitudes of the planet. The Earth’s atmospheric, marine and river currents carry tonic contaminants from the industrial mid-latitudes to the Arctic Region.

Once deposited in the Arctic, unique conditions, such as long periods of darkness and extreme temperatures, act to extend significantly the "shelf life" of contaminants. The powerful impact of air and waterborne pollution is being felt not only in the health of the animals, such as the polar bear and seal, but in human beings as well.