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POPSMap Of Active Lakes Below Antarctic Ice For some Antarctic lakes, pressure exerted by the ice above forces its water to fill an adjacent lake. The movement results in elevation changes at the surface over both lakes, detectable by NASA satellites. Credit: NASA Goddard's Scientific Visualization Studio Understanding this plumbing is important, as it can lubricate glacier flow and send the ice speeding toward the ocean, where it can melt and contribute to sea level change. But figuring out what's happening beneath miles of ice is a challenge. Researchers led by Smith analyzed 4.5 years of ice elevation data from NASA's Ice, Cloud and land Elevation satellite (ICESat) to create the most complete inventory to date of changes in the Antarctic plumbing system. The team has mapped the location of 124 active lakes, estimated how fast they drain or fill. Read more.
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POPSLatest Antarctic Sea Ice Extent ''it is mid-summer in the Southern Hemisphere. Ice extent remains well (one million square kilometers) above the 28 year average and an impressive 3 million square kilometers above last year at this time!. There is clearly a lot of year to year variability in the record but the demise of the Antartic icecap seems to be anything but imminent. Most of the warming and melt in recent years has been in the vicinity of the Antarctic Peninsula, a small portion of the Antarctic which reaches above the Antarctic Circle and is a choke-point for the circumpolar ocean currents, and is more susceptible to variations. There’s also an active subsea volcano in the area, perhaps leading to the warm water upwelling in the study''
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POPSMassive volcano exploded under Antarctic icesheet
Evidence for this comes from a British-American airborne geophysical survey in 2004-5 that used radar to delve deep under the ice sheet to map the terrain beneath. Vaughan's team spotted anomalous radar reflections over 23,000 square kilometres (8,900 sq. miles), an area bigger than Wales. They interpret this signal as being a thick layer of ash, rock and glass, formed from fused silica, that the volcano spewed out in its fury. The amount of material -- 0.31 cubic kilometres (0.07 cubic miles) -- indicates an eruption of between three and four on a yardstick called the Volcanic Explosive Index (VEI). By comparison, the eruption of Mount St. Helens in 1980, which was greater, rates a VEI of five, and that of Mount Pinatubo in 1991 is a VEI of six. "We believe this was the biggest eruption in Antarctica during the last 10,000 years," BAS' Hugh Corr says. "It blew a substantial hole in the icesheet and generated a plume of ash and gas that rose around 12 kms (eight miles
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