Contrasting climate change in the two polar regions

• Published in: Polar Research
• Main Authors: Turner, John, Overland, Jim
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley-Blackwell 2009
• Subjects: Meteorology and Climatology; Glaciology; Arctic; Antarctic; Southern Ocean; The Antarctic; Arctic Ocean; Antarctic Peninsula; East Antarctica; West Antarctica; albedo; Antarc*; Antarctica; Climate change; Ice; permafrost; Polar Research; Sea ice
• Online Access: http://nora.nerc.ac.uk/id/eprint/11331/; https://nora.nerc.ac.uk/id/eprint/11331/1/6120-16406-1-PB.pdf; https://doi.org/10.1111/j.1751-8369.2009.00128.x

The two polar regions have experienced remarkably different climatic changes in recent decades. The Arctic has seen a marked reduction in sea-ice extent throughout the year, with a peak during the autumn. A new record minimum extent occurred in 2007, which was 40% below the long-term climatological mean. In contrast, the extent of Antarctic sea ice has increased, with the greatest growth being in the autumn. There has been a large-scale warming across much of the Arctic, with a resultant loss of permafrost and a reduction in snow cover. The bulk of the Antarctic has experienced little change in surface temperature over the last 50 years, although a slight cooling has been evident around the coast of East Antarctica since about 1980, and recent research has pointed to a warming across West Antarctica. The exception is the Antarctic Peninsula, where there has been a winter (summer) season warming on the western (eastern) side. Many of the different changes observed between the two polar regions can be attributed to topographic factors and land/sea distribution. The location of the Arctic Ocean at high latitude, with the consequently high level of solar radiation received in summer, allows the ice-albedo feedback mechanism to operate effectively. The Antarctic ozone hole has had a profound effect on the circulations of the high latitude ocean and atmosphere, isolating the continent and increasing the westerly winds over the Southern Ocean, especially during the summer and winter.