The North Pole is significantly warmer than the South Pole because it lies at sea level in the middle of an ocean (which acts as a reservoir of heat), rather than at altitude in a continental land mass.
Winter (January) temperatures at the North Pole can range from about −43 °C (−45 °F) to −26 °C (−15 °F), perhaps averaging around −34 °C (−29 °F). Summer temperatures (June, July and August) average around the freezing point (0 °C (32 °F)).
The sea ice at the North Pole is typically around 2 to 3 m (6 ft 7 in to 9 ft 10 in) thick, though there is considerable variation and occasionally the movement of floes exposes clear water. Studies have shown that the average ice thickness has decreased in recent years. Many attribute this decrease to global warming, though this conclusion is disputed by some. Reports have also predicted that within a few decades the Arctic Ocean will be entirely free of ice in the summer months. This may have significant commercial implications; see "Territorial Claims," below.
Temperature changes vary over the globe. Since 1979, land temperatures have increased about twice as fast as ocean temperatures (0.25 °C per decade against 0.13 °C per decade). Ocean temperatures increase more slowly than land temperatures because of the larger effective heat capacity of the oceans and because the ocean loses more heat by evaporation. The Northern Hemisphere warms faster than the Southern Hemisphere because it has more land and because it has extensive areas of seasonal snow and sea-ice cover subject to ice-albedo feedback. Although more greenhouse gases are emitted in the Northern than Southern Hemisphere this does not contribute to the difference in warming because the major greenhouse gases persist long enough to mix between hemispheres.
http://en.wikipedia.org/wiki/North_Pole
http://en.wikipedia.org/wiki/Global_warming
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