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oceanresearch Antarctic Sea Ice Drift Shown To Cause Sea Ice Cover Increase NASA and British Antarctic Survey scientists have reported in Nature Geosciences in November the frst direct evidence that changes to Antarctic sea ice drift, caused by changing winds, are responsible for increases in Antarctic sea ice cover in the past two decades. This helps explain why Antarctic sea ice cover has increased under the effects of climate change. Research scientists Ron Kwok of NASA's Jet Propulsion Laboratory (JPL) and Paul Holland of the Natural Environment Research Council's British Antarctic Survey used maps created by JPL from more than 5 million daily ice-motion measurements. The data, captured over a period of 19 years by four U.S. satellites, show for the frst time long-term changes in sea ice drift around Antarctica. "The total Antarctic sea ice cover is increasing slowly, but individual regions are actually experiencing much larger gains and losses that are almost offsetting each other overall," Holland said. These regional changes are caused by wind changes, which affect the ice cover through changes in ice drift and air temperature. "The changes in ice drift also suggest large changes in the ocean surrounding Antarctica, which is very sensitive to the cold and salty water produced by sea ice growth," he said. Increased northward winds have caused the sea ice cover to expand outwards from Antarctica in regions. The Arctic, by contrast, has been losing sea ice dramatically, but the Arctic Ocean is surrounded by land, so changed winds cannot cause Arctic ice to expand in the same way as what is occurring with Antarctic sea ice. The new research will improve understanding of present and future climate change. One-Third of Marine Species Yet To Be Discovered, Study Finds There are fewer than 1 million marine species on the planet, lower than some previous estimates, with about one-third still undiscovered, according to a study published in November in Current Biology. Hot spots for fnding new species include deep-sea ecosystems and tropical areas, said researcher Mark Costello from the University of Auckland. "If we look at the number of undescribed species and samples from around the world, especially deep-sea and tropical areas, the average over 100 studies was that about 30 percent of those new species were new to science," Costello told The New Zealand Herald. New species found in the past year include Yoda purpurata in the North Atlantic, named after the "Star Wars" Jedi master, a crimson shrimp at 2,600 meters depth in the Norwegian Sea and a bristle worm at 1,600 meters below the northeast Pacifc. Complementing this research, the World Register of Marine Species is an open-access, online database that has received contributions from almost 300 scientists from 32 countries. Species research enables more accurate estimates of extinction rates through habitat loss. 74 st / DECEMBER 2012 www.sea-technology.com