So researchers need to look elsewhere for clues
of ice sheet melt in the more distant past.
The paper also describes an atmosphere - ocean modeling study of feedback loops caused
by ice sheet melting under 2 °C conditions.
Since the last of the
continental ice sheet melted over 10,000 years ago the world has warmed for about 5,000 years and has been on a long cooling trend ever since.
The paper also describes an atmosphere - ocean modeling study of feedback loops caused by
ice sheet melting under 2 °C conditions.
But it was long suspected that «orbital factors» weren't the whole story, as the southern hemisphere
ice sheets melted back at the same time as the northern ones.
During that time, temperatures were less than 1 °C warmer than they are today, but sea level stood about 5 to 9 meters higher due to large -
scale ice sheet melt.
That is: Is there
ice sheet melting data out there that was not published because it seemed inconsistent with sea level data?
Worst case scenarios
of ice sheet melting and sliding lead to estimates of sea - level rise of the worrying 4 to 6 m.
During that time, temperatures were less than 1 °C warmer than they are today, but sea level stood about 5 to 9 meters higher due to large -
scale ice sheet melt.
With both the Greenland and West
Antarctic ice sheets melting at an accelerating pace, sea level could rise by up to six feet during this century.
«West Greenland
Ice Sheet melting at the fastest rate in centuries: Weather patterns and summer warming trend combine to drive dramatic ice loss.»
The Greenland ice sheet did not melt as much as expected during a recent warming period but that may mean Antarctic
ice sheets melted more than expected
[Response: Here's a simple back - of - envelope consideration for the future: if the Greenland
ice sheet melts completely over the next ~ 1,000 years (Jim Hansen argues in the current Climatic Change that the time scale could be centuries), this would contribute an average flux of ~ 0.1 Sv of freshwater to the surrounding ocean.
Häkkinen, S., D. K. Hall, C. A. Shuman, D. L. Worthen, and N. E. DiGirolamo 2014: Greenland
Ice Sheet melt from MODIS and associated atmospheric variability.
A warming climate could also increase algal growth in the future, potentially boosting algae's influence
on ice sheet melting, he said.
Our civilizations began building immediately after the last great continental
ice sheets melted about 10,000 years ago, thanks to agricultural success.
Greenland is more than twice as large as Texas and if the
entire ice sheet melted, scientists estimate global sea levels would rise roughly 24 feet.
``... studies continue to argue that the past ratio of arctic temperature rise and GAT, as well
ice sheet melt rates, will also be valid in the future.
The next step will see the team analysing sediment samples to determine how quickly the East Antarctic
ice sheet melted during the Pliocene.
How alarming depends on how quickly the
great ice sheets melt in response to warming — and that is another big unknown.
Bamber has recalculated the critical threshold temperature
for ice sheet melting by forcing two surface mass balance models with real future climate.
The areas of doubt are there — how fast will the West
Antarctica Ice Sheet melt — but these are doubts in the particulars not in the general proposition.
According to the research, freshwater from land -
based ice sheets melting into the oceans is inducing feedback that is accelerating the melting of ice shelves — a loop that indicates sea level rise will continue and could be devastating at much lower temperature changes than previously thought.
The rate at
which ice sheets melt is difficult to understand, because there are many processes that occur.
The large Eemian sea level excursions imply that substantial
ice sheet melting occurred when the world was little warmer than today.
Items covered How the climate is changing with time laps charts showing the changes in Sea ice
melting Ice sheet melting Carbon dioxide in the atmosphere Global temperature change Students will also explore a future technology on how to reduce the human impact on the environment.
This entry was posted on Wednesday, August 15th, 2012 at 9:56 am and is filed under
ice sheet melt factor.
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