Deadly Russian Heat Wave
The brutal heat wave that has gripped Russia may ultimately be responsible for the deaths of 15,000 people, according to Weather Underground meteorologist Jeff Masters. The map above, from the NASA Earth Observatory Picture of the Day website, shows how the temperature on July 27 departed from the 2000 to 2008 average. Deadly concentrations of record-breaking heat in Russia, Siberia and also parts of China are depicted in orange and red tones. (The map is based on data from the Moderate Resolution Imaging Spectroradiometer, or MODIS, on NASA’s Terra satellite.)
Giant Ice Island Calves from Greenland Glacier
On August 17, 2010, a chunk of ice four times the size of Manhattan calved from the Petermann Glacier on the northwestern coast of Greenland, as seen in the picture above, also from the NASA Earth Observatory Picture of the Day site. The newly born ice island represents about a quarter of the 40-mile length of the glacier’s floating ice shelf.
“Calving is a natural process,” says Robert Bindschadler, a senior research scientist at NASA’s Goddard Space Flight Center. But he also notes that changes in calving will occur as the climate changes.
Ice from Greenland’s massive ice cap flows outward and toward the sea through relatively narrow fjords along the coast. But whether Greenland loses or gains ice over time — which will determine how much it contributes to sea level rise — depends on a complex balance between the accumulation of of snow on the ice cap and how much ice is lost to melting, and calving from the glaciers.
In 2006, researchers reported widespread acceleration of Greenland glaciers below 66° degrees north; by 2005, that acceleration had expanded to 70° north. “Accelerated ice discharge in the west and particularly in the east doubled the ice sheet mass deficit in the last decade from 90 to 220 cubic kilometers per year,” the researchers wrote in the journal Science. “As more glaciers accelerate farther north, the contribution of Greenland to sea-level rise will continue to increase.”
Recent Comments