The cryosphere is those portions of Earth's surface where water is in solid form, including sea ice, lake ice, river ice, snow cover, glaciers, ice caps, ice sheets, and frozen ground. The cryosphere is an integral part of the global climate system with important links and feedbacks generated through its influence on surface energy and moisture fluxes, clouds, precipitation, hydrology, atmospheric and oceanic circulation.
Snow and ice help keep the earth cool by reflecting between
60% and 90% of the solar energy that shines on them back into
space. Reduction of snow cover and sea ice may lead to increased
warming, as more solar energy is absorbed.
The two more important areas ase the Antarctica and Greenland which are the 99% of glacier ice on Earth. The major body of land ice in the Arctic – the Greenland ice sheet – has been found to be thickening inland. Nearer the coast, however, the ice sheet is thinning and shrinking, at an accelerating rate. Overall, the Greenland ice sheet has been found to be losing ice mass over the last twenty years, and this ice loss is becoming faster. Antarctic ice consists of a land mass topped by an ice sheet and surrounded by sea ice. Antarctic sea ice extentis increasing at around 1% per decade, thought to be caused by shifting weather patterns reacting to changes in ozone, high in the atmosphere.
The two more important areas ase the Antarctica and Greenland which are the 99% of glacier ice on Earth. The major body of land ice in the Arctic – the Greenland ice sheet – has been found to be thickening inland. Nearer the coast, however, the ice sheet is thinning and shrinking, at an accelerating rate. Overall, the Greenland ice sheet has been found to be losing ice mass over the last twenty years, and this ice loss is becoming faster. Antarctic ice consists of a land mass topped by an ice sheet and surrounded by sea ice. Antarctic sea ice extentis increasing at around 1% per decade, thought to be caused by shifting weather patterns reacting to changes in ozone, high in the atmosphere.
As
Earth warms the sea level rise, it means that about 65 meters of sea
level is potential to rise if mountain glaciers and ice caps melt. Furthermore, the impact of melting sea ice amplifies the warming in the artic and the hounting grounds of polar bear will be reduced.
Changes in the glaciers in the Greater Himalaya .
The glaciers of the Himalaya are the Third Pole. They feed the giant rivers of Asia, and support half of humanity.
According to the Intergovernmental Panel on Climate Change (IPCC),
“glaciers in the Himayalas are receding faster than in any other part of
the world and if the present rate continues, the likelihood of them
disappearing by the year 2035 and perhaps sooner is very high if the
earth keep getting warmer at the current rate”.
Links:
http://na.unep.net/geas/getuneppagewitharticleidscript.php?article_id=91
http://www.navdanya.org/climate-change/in-the-himalayas
http://wwf.panda.org/what_we_do/where_we_work/eastern_himalaya/threats/climate/
THE OCEAN
Sice industrial revolution carabon dioxide leves have been increasing. Ocean plays a really important play in the carbon cycle, it absorbs almost a third of the atmospheric carbon dioxide. The carbon dioxide reacts with water to form carbonic acid that dissociates into bicarbonate and hydrogen ions. The concentration of the hydrogen ions determines the pH of the sea. So, if more carbon dioxide is absorbed by ocean the pH of the ocean will descend more in the next years.
Many marine organisms that produce calcium carbonate shells or skeletons are negatively impacted by increasing CO2 levels and decreasing pH in seawater. A more acidic environment has a dramatic effect on some calcifying
species, including oysters, clams, sea urchins, shallow water corals,
deep sea corals, and calcareous plankton. It means that the ability of reef-building corals to produce their skeletons can be reduced or even that the shells can be dissolved. When shelled organisms are at risk, the entire food web may also be at risk.
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