Dust may settle unanswered questions on AntarcticaMarch 30, 2009Dust trapped deep in Antarctic ice sheets is helping scientists unravel details of past climate change. Researchers have found that dust blown south to Antarctica from the windy plains of Patagonia - and deposited in the ice periodically over 80,000 years - provides vital information about glacier activity. Scientists hope the findings will help them to better understand how the global climate has changed during the past ice age, and so help predict environmental changes in the future. The study indicates that the ebb and flow of glaciers in the Chilean and Argentinian region is a rich source of information about past climates - which had not until now been fully appreciated by scientists. The study, carried out by the Universities of Edinburgh, Stirling and Lille, shows that the very coldest periods of the last ice age correspond with the dustiest periods in Antarctica's past. During these times, glaciers in Patagonia were at their biggest and released their meltwater, containing dust particles, on to barren windy plains, from where dust was blown to Antarctica. When the glaciers retreated even slightly, their meltwater ran into lakes at the edge of the ice, which trapped the dust, so that fewer particles were blown across the ocean to Antarctica. Dust from the ice cores was analysed and found to be a close match with mud of the same age in the Magellan Straits, showing that most of the dust originated in this region. The study was supported by the Natural Environment Research Council. The findings were published in Nature Geoscience. Professor David Sugden, of the University of Edinburgh, said: "Ice cores from the Antarctic ice sheet act as a record of global environment. However, the dust levels showed some sudden changes which had us puzzled - until we realised that the Patagonian glaciers were acting as an on/off switch for releasing dust into the atmosphere." University of Edinburgh |
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| Related Antarctica Current Events and Antarctica News Articles Oceans' uptake of manmade carbon may be slowing The oceans play a key role in regulating climate, absorbing more than a quarter of the carbon dioxide that humans put into the air. New fossil plant discovery links Patagonia to New Guinea in a warmer past Fossil plants are windows to the past, providing us with clues as to what our planet looked like millions of years ago. West Antarctic ice sheet may not be losing ice as fast as once thought New ground measurements made by the West Antarctic GPS Network (WAGN) project, composed of researchers from The University of Texas at Austin, The Ohio State University, and The University of Memphis, suggest the rate of ice loss of the West Antarctic ice sheet has been slightly overestimated. Last time carbon dioxide levels were this high: 15 million years ago, scientists report You would have to go back at least 15 million years to find carbon dioxide levels on Earth as high as they are today, a UCLA scientist and colleagues report Oct. 8 in the online edition of the journal Science. NASA flies to Antarctica for largest airborne polar ice survey NASA begins a series of flights Oct. 15 to study changes to Antarctica's sea ice, glaciers and ice sheets. The flights are part of Operation Ice Bridge, a six-year campaign that is the largest airborne survey ever made of ice at Earth's polar regions. Peering under the ice of a collapsing polar coast Starting this month, a giant NASA DC-8 aircraft loaded with geophysical instruments and scientists will buzz at low level over the coasts of West Antarctica, where ice sheets are collapsing at a pace far beyond what scientists expected a few years ago. Laser technique has implications for detecting microbial life forms in Martian ice An innovative technique called L.I.F.E. imaging used successfully to detect bacteria in frozen Antarctic lakes could have exciting implications for demonstrating signs of life in the polar regions of Mars. Algae and pollen grains provide evidence of remarkably warm period in Antarctica's history For Sophie Warny, LSU assistant professor of geology and geophysics and curator at the LSU Museum of Natural Science, years of patience in analyzing Antarctic samples with low fossil recovery finally led to a scientific breakthrough. Global public health the focus of scientific conference Counterfeit and adulterated food and drugs and advances in measurement science used to detect them emerged as key themes of the Annual Scientific Meeting (ASM) hosted by the U.S. Pharmacopeial (USP) Convention. MSU scientist helps map potato genome; move will improve crop yield It's been cultivated for at least 7,000 years and spread from South America to grow on every continent except Antarctica. Now the humble potato has had its genome sequenced. More Antarctica Current Events and Antarctica News Articles |
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