Ice Sheets
The total volume of ice sheets on the surface of the Earth is equivalent to 70 m of water, or 1.8% of the global water content. is high for precipitation, but low for vapor (since 18O is heavier and will preferentially remain in a liquid).
Ice sheets contain a record of hundreds of thousands of years of past climate, trapped in the ancient snow. Scientists recover this climate history by drilling cores in the ice, some of them over 3,500 meters (11,000 feet) deep.
Ice sheets that form during glaciations cause erosion of the land beneath them. After some time, this will reduce land above sea level and thus diminish the amount of space on which ice sheets can form.
With this discovery, came the realization that movement of ice sheets might act to concentrate meteorites in certain areas.
The general term "ice age" or, more precisely, "glacial age" denotes a geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, resulting in an expansion of continental ice sheets, ...
In the outer regions of the ice sheets, the researchers reported large areas of thinning, with the rate of thinning increasing rapidly towards the ocean.
Further note: The sea-bottom results have now been compared to hydrogen isotope ratios in deep boreholes in the ice sheets of Antarctica, which took nearly a million years to accumulate (Science, 11 June 2004, p. 1609).
CRYOSPHERE - Portion of Earth which consists of the ice masses and snow deposits (continental ice sheets, mountain glaciers, sea ice, surface snow cover and lake/river ice).
The Moon's water ice is not concentrated in polar ice sheets. Rather, it seems to be in very low amounts distributed across a significant number of craters in the polar regions. The water probably is only 0.
This is predicted to produce changes such as the melting of glaciers and ice sheets, more extreme temperature ranges, significant changes in weather conditions and a global rise in average sea levels.
Human geography ...
It is now possible to advance theories as to the origin of this ice, and it is believed that the deposits may have been emplaced by the retreat of regional ice sheets.
Then George Stanley, a geologist of Fresno State College in California, suggested the stones might become frozen in ice sheets during the winter and slide around with the sheets on an underlying slick of water.
Included are small mountain glaciers as well as ice sheets continental in size, and ice shelves which float on oceans but are fed in part by ice formed on land. Used for active glaciers and advancing glaciers.
 See also: Earth, Ocean, Year, Period, Time
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