The East Antarctic Ice Sheet (EAIS) is one of two large ice sheets in Antarctica, and the largest in the entire world. It rests upon a large land mass, contrary to that of the West Antarctic Ice Sheet (WAIS), which rests on frozen water. The larger of the two, the EAIS lies between 45 o West and 168 o East longitudinally. The EAIS is separated from the WAIS by the Transantarctic Mountains.
The East Antarctica Ranges are a group of mountain ranges situated on the EAIS. The East Antarctic two-thousanders are the 29 known peaks within these ranges whose summits reach or exceed 2000 meters above sea level.
The EAIS is also home to the thickest point on the Antarctic continent, at 15,700 ft (4,800 m). Most well known, however, is that the EAIS is home to the South Pole (commonly mistaken for the Magnetic South Pole.)
Ice mass changes
Current international focus on global warming issues has drawn attention to the melting of the polar ice caps. According to researchers at the University of Michigan, satellite radar altimeter data indicate that the EAIS interior area is actually gaining mass at a rate of 45 billion tonnes per year while a GRACE-based study found that the total Antarctic ice sheet (including WAIS, and EAIS coastal areas) is losing mass at a rate of 152 cubic kilometers (ca 139 billion tonnes) per year.
Temperature changes
Cooling in East Antarctica during the decades of the 1980s and 1990s partially offset warming of the West Antarctic ice sheet which has warmed by more than 0.1°C/decade in the last 50 years. The continent-wide average surface temperature trend of Antarctica is positive and significant at >0.05°C/decade since 1957.
Territorial claims
In spite of the Antarctic Treaty, many countries hold a claim on portions of Antarctica. Within EAIS, the United Kingdom, France, Norway, Australia, Chile and Argentina all claim a portion (sometimes overlapping) as their own territory.
From http://en.wikipedia.org/
Saturday, July 11, 2009
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