Polar ice caps are high-latitude areas completely covered in ice that occur in the polar regions of Earth. Other planets, such as Mars, for example, have polar ice caps also, but unlike Earth’s ice, which is largely composed of frozen water, Mars’ ice is mostly made up of frozen carbon dioxide. Polar areas receive less solar energy from the sun and are therefore subject to low surface temperatures, allowing ice caps to form.
A Short Untamed Science Video about Global Warming
Are Polar Ice Caps Static?
Ice cap formation is largely dependent on the amount of energy a polar region receives in the form of solar radiation, which can change depending on season, climate fluctuation, geologic time, or a combination of all three. Ice caps can expand or retract, hence how ice ages come and go.
As the deserts of the equatorial region of Africa are one extreme of the Earth, the polar ice caps of the Arctic and Antarctic are extreme in the opposite respect.
North vs. South: Differences in the Poles
The North and South Poles, while similar in regard to their frigid climate and extreme conditions, are actually very different geographically. The North Pole is actually a body of water, the Arctic Sea, which for the most part, remains covered in floating pack ice. In some areas of the sea, the ice freezes at a thickness upward of several meters thick and forms expansive, contiguous sheets of ice. During the warmer months of the year, some of the sea ice melts, and the polar ice caps of the North Pole retreat further north. The South Pole, on the other hand, is comprised of the continent of Antarctica, a giant ice sheet that stays in tact year-round. Data from the past several decades has shown that polar ice in the North Pole is on the decline, while ice in the South Pole is slightly, but steadily, increasing.
The continent of Antarctica is sometimes referred to as a cold desert-- a desert is determined not by temperature, but by the average amount of precipitation it receives per year, and since Antarctica gets relatively minimal precipitation each year, it is technically a desert, and a cold one at that!
Is an Ice Cap the same as a Glacier?
In short—no. Polar ice caps are large accumulations of ice that form over bodies of water while glaciers are large concentrations of ice that form on land. Glaciers form when accumulations of snow and frozen precipitation exceed the amount of melted snow in an area. Over an extensive period of time, this frozen precipitation compacts, transforms into ice, and forms a glacier.
Is there Life on Polar Ice Caps?
At the farthest reaches of the poles, where ice is ubiquitous and permanent, conditions are too extreme to sustain life. Even bacteria, organisms known to inhabit the most extreme of environments, are absent. However, the less extreme (comparatively speaking) areas of the Arctic and Antarctic do support some forms of life. These animals all share one thing in common—their ability to generate
their own body heat. This is extremely important, as temperatures in the poles are not warm enough to sustain exothermic animals like insects, amphibians, or reptiles. The birds and mammals that inhabit the poles spend the majority of their time eating in order to obtain enough calories to keep their body heat up. They all depend, either directly, or indirectly, on food from the sea. The Arctic is home to terrestrial mammals such as foxes, polar bears, caribou, ground squirrels, wolves, wolverines, ermines, and musk oxen. There are also marine mammals (walruses, seals, and whales) and a variety of raptors and seabirds. The Antarctic is home to penguins, a few seabirds, and seals.
A short montage of Polar Icecaps footage from Alaska by Hilary Hudson
Fun Facts about Polar Ice Caps
- 70% of the Earth’s fresh water is locked in the frozen continent of Antarctica
- The average thickness of the ice on Antarctica is over a mile!
- At the poles, during the winter, the sun never truly rises, and in the summer, never sets