So what has reallychanged? The data has been adjusted better this time around? Antarctica is presently at maximum ice extent or pulse.
Of course the Northernhemisphere remains half a degree warmer and this allows a blanketloss of ice. Could someone explain just what part of Greenland ispresently losing more ice than snow is adding and the reverse? Howfar has this boundary retreated?
Historically, these warmperiods usually are good for a couple of decades at least before theyreverse. Since it has become clear that CO2 is not a driver, itremains to the historical record to inform us.
What would really ruin myday is to see an abrupt return to conditions of two centuries ago.
Polar Ice Loss Increased‘Five-Fold’ in 20 Years
Researchers say study is mostaccurate to date
http://www.theepochtimes.com/n2/world/polar-ice-loss-increased-five-fold-in-20-years-320224.html
Over the past twodecades, ice melting in Greenland and Antarctica caused an11-millimeter rise in the world’s sea levels, according to a newstudy compiled by researchers who say it is the most accuratemeasurement of ice loss to date.
“Both ice sheetsappear to be losing more ice now than 20 years ago, but the paceof ice loss from Greenland is extraordinary, with nearly a fivefoldincrease since the mid-1990s,” stated Erik Ivins ofNASA’s Jet Propulsion Laboratory, who helped lead the study. “Incontrast, the overall loss of ice in Antarctica has remained fairlyconstant, with the data suggesting a 50 percent increase inAntarctic ice loss during the last decade.”[? - arclein]
Published in thejournal Science on Thursday, led by scientists at the Universityof Leeds, and involving 47 researchers, the study used aircraftand 10 different satellites to measure the ice and its rate of melt.The research was backed by the European Space Agency and NASA.
The 11.1-millimeter,or 0.47-inch rise in sea levels from the polar ice sheets makes up afifth of the total rise over the survey period. The remaining sealevel rise was caused by ice melt in other places, such as glaciersand ice caps, the expansion of the warming oceans, and by groundwatermining, according to the release.
The overall rate ofmelting of the ice sheets in both Greenland and Antarctica hasincreased over time. They are now shedding more than three times asmuch ice—contributing to 0.95 mm rise in sea level per year—thanin the 1990s, when both were losing the equivalent of 0.27 mm peryear.Advertisement
Together, the two areas lose around 344 billion tons of iceeach year, researchers estimate, and of that, Greenland’s share isaround 263 billion tons, which was about what they expected. Theremainder was lost in Antarctica.
In previous years,there was a disagreement about the amount of ice lost, especiallyin Antarctica. Some studies showed massive ice loss and others evenshowed a gain in ice.
In this latest study,researchers were able to “reconcile the differences” amongnumerous previous studies on the matter, a release from LeedsUniversity states.
One of the issues withmeasuring ice loss is the remoteness of the locations—Greenland ismostly uninhabited and Antarctica is entirely uninhabited, save a fewscientists—and the massive size of the ice sheets. Scientists alsohave to differentiate between snow and ice.
The scientists saidthe newest study’s data is consistent with climate changepredictions laid out in the 2007 Intergovernmental Panel on ClimateChange. However, the latest data offers clarity that the 2007 studydid not.
“Without theseefforts, we would not be in a position to tell people with confidencehow Earth’s ice sheets have changed, and to end the uncertaintythat has existed for many years,” said professor Andrew Shepherd,head of the study.
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