At a glance, Earth’s polar regions may seem like mirror images located some 12,000 miles apart. Both are vast, icy regions covering opposite ends of the globe. Animal life is scarce, human inhabitants are few and there is little to spark scientific imagination.

Closer examination, however, reveals many differences as well as similarities between the Earth’s poles.

To the south, the continent of Antarctica is a landmass roughly the size of the United States and Mexico combined. It is depressed into the Earth’s crust by a sheet of ice roughly 2 miles thick. A few thousand scientists and support personnel, the continent’s recent and only human inhabitants, live at a handful of research stations across the continent. Few live there year-round.

The South Pole lies deep in the Antarctic interior, roughly 900 miles from the nearest U.S. scientific station on Ross Island, near the Antarctic Coast.

To the north, an imaginary ring, known as the Arctic Circle, defines the area surrounding the landless North Pole. The region inside the Arctic Circle covers vast swathes of the northern reaches of Canada, Greenland, Scandinavia and Russia.

It is therefore, home to human populations of varied size and complexity when compared with their southern counterparts. Scientists have begun collaborating with native inhabitants, who have lived and subsisted in the region for millennia, on observations of sea-ice thickness, animal populations and other natural factors to build a holistic view of the Arctic climate, past and present

Because the ice that covers the Arctic Ocean and the North Pole breaks up and re-forms with the seasons, much of the northern Arctic is inaccessible to most scientists for many months.

Through NSF's Office of Polar Programs (OPP), the agency plays a key role in managing scientific endeavors in the polar regions. In its capacity as chair of the Interagency Arctic Research Policy Committee (IARPC), NSF acts as the lead agency for implementing Arctic research policies. NSF also manages the U.S. Antarctic Program, which coordinates almost all U.S. science on the continent, including research carried out by other federal agencies.

OPP supports research in a range of disciplines, from biology to astrophysics and from social science to oceanography. The polar regions provide scientists with immense "natural laboratories" to study some of the most basic questions.

	How did the universe begin? - Telescopes at the South Pole and balloon flights around Antarctica allow scientists to conduct long-term observations of the origins of the universe and of some of its smallest constituent particles.
	Is the global climate changing? How and why? - Scientists cross the Antarctic ice sheet by tractor-train to sample ice that holds clues to the climate of the past 200 years, while at the North Pole, a string of instruments as long as Mt. Rainer is high, tracks ongoing changes in theArctic Ocean.
	What are the limits of life in extreme environments? - Microbes may thrive at the South Pole, despite bitter cold, darkness and extreme doses of ultraviolet radiation, while other microbes may live in frozen lakes. How do they survive? And what can we learn from these "extremophiles" that might provide wider biological insights?