Antarctica is the highest, driest, coldest, windiest and brightest of the seven continents. It is roughly the size of the United States and Mexico combined and is almost completely covered by a layer of ice that averages more than one mile in thickness, but is nearly three miles thick in places. This ice accumulated over millions of years through snowfall. Presently, the Antarctic ice sheet contains 90% of the ice on Earth and would raise sea levels worldwide by over 200 feet were it to melt.

The ground beneath the Antarctic ice sheet is a mixture of mountains, plains, and ocean basins. The tallest mountains extend above the ice sheet. The longest mountain range is the Transantarctic Mountains that conveniently divide the continent into a large sector in the eastern hemisphere, called East Antarctica, and a smaller sector in the western hemisphere, called West Antarctica. The Antarctic Peninsula is primarily a second mountain range. The highest mountain summit is the Vinson Massif at 16,062 feet above sea level.

Gravity exerts sufficient force on the ice that the ice sheet moves. The highest elevation ice is in the interior despite precipitation rates of less than one inch per year. This ice is very cold and slow. Flow rates increase toward the coast as glaciers are formed. Some glaciers flow directly into the ocean while others join to form large, thick floating ice shelves. The Pine Island Glacier, flowing at over 10,000 feet per year, is believed to be the fastest Antarctic glacier. And the largest ice shelf is the Ross Ice Shelf, roughly the size of Texas.

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