Water worldU.S. researchers breach Antarctic subglacial lake in search for extreme lifePosted January 28, 2013
In the end, it took a little bit of magic and quite a lot of effort, but U.S. scientists announced this week that they successfully reached a lake buried nearly a kilometer below the West Antarctic Ice Sheet. Previous Coverage
The moment came on Jan. 27 (local New Zealand time) when scientists and drillers with the Whillans Ice Stream Subglacial Access Research Drilling (WISSARD) project used a custom-made, high-powered hotwater drill to bore through 800 meters of ice to reach subglacial Lake Whillans. The researchers will spend the rest of the week retrieving water and sediment samples from the lake, which may contain microscopic life that scientists will study to learn about how organisms evolve in such extreme environments. The interdisciplinary project will also collect data to understand fundamental questions about climate history and ice sheet dynamics in Antarctica. The effort marks the first successful retrieval of clean whole samples from an Antarctic subglacial lake, according to a press release from the WISSARD team. Photo Credit: WISSARD
WISSARD chief scientist John Priscu prepares a camera to go down the borehole.
“WISSARD’s groundbreaking exploration of Antarctica’s subglacial environment marks the beginning of a new era in polar science, opening the window for future interdisciplinary scientific investigations of one of Earth’s last unexplored frontiers,” the team said in a joint statement. Science journalist Doug Fox, embedded with the project and reporting for Discover magazine, wrote from the field that the subglacial lake has already offered up some surprises — and results. For instance, Fox wrote that the lake is only a couple of meters deep, much less than expected based on earlier surveys using seismic instruments to image the subglacial lake through the ice sheet. However, the big news appears to be the discovery of diatoms from mud that was stuck to the hotwater drill nozzle after it penetrated into the lake. The mud, Fox wrote, was smeared out on slides and viewed under a microscope at on-site lab. The sample revealed what Fox called “the clear glassy shells” of dead diatoms, photosynthetic organisms that would have lived in the upper, light-filled waters when it was a shallow sea not covered by ice. “Those diatoms are only a first glimpse — fortuitously salvaged from the drill. But Lake Whillans is also being sampled for present-day life. Those results are still to come,” Fox concluded in his field report on Discover magazine’s website. This week’s achievement is the culmination of more than a decade of international and national planning and more than three years of project preparation by the WISSARD consortium of U.S. universities and two international contributors. There are 13 WISSARD principal investigators representing eight different U.S. institutions. The penetration of the lake follows a tense week of weather delays that prevented the scientists and drillers from reaching the field camp, located near the Texas-sized Ross Ice Shelf. The first couple of weeks in January were spent hauling the hotwater drill equipment and scientific cargo across the ice shelf with tractors. The researchers will have until the end of this week to sample the lake before flying back to McMurdo Station , where the operation underwent a comprehensive test in December. The National Science Foundation , which manages the U. S. Antarctic Program , provided more than $10 million in grants for the project, which was originally part of the International Polar Year , a global scientific campaign that ran from 2007 to 2009. The U.S. triumph follows a failed attempt by the British Antarctic Survey (BAS) last month to reach subglacial Lake Ellsworth after a similar hotwater drilling operation failed to bore through the ice properly. Meanwhile, Russia’s Arctic and Antarctic Research Institute announced earlier in January that its scientists had obtained the first sample of transparent ice from the water of Lake Vostok, the largest subglacial lake in Antarctica. While all three projects are studying subglacial lakes, each environment is different. Lake Vostok is believed to have been isolated for millions of years. Lake Ellsworth may have occupied an ancient fjord for hundreds of thousands of years. Lake Whillans is more like a wetland, with the lake periodically filling and draining. NSF-funded research in this story: John Priscu, Mark Skidmore and Andrew Mitchel, Montana State University, Award No. 0838933 ; Slawek Tulaczyk, University of California-Santa Cruz, Award Nos. 0839142, 0838947 ; Ross Powell and Reed Scherer, Northern Illinois University, Award Nos. 0839107, 0839059 ; Ross Virginia and Jill Mikucki, Dartmouth College, Award No. 0838896 ; Brent Christner, Louisiana State University, Award No. 0838941 ; Jeffrey Severinghaus and Helen Fricker, University of California-San Diego Scripps Institution of Oceanography, Award No. 0838885 ; Robert Jacobel, Saint Olaf College, Award Nos. 0838855, 0838854 ; Sridhar Anandakrishnan, Pennsylvania State University, Award No. 0838763, 0838764 ; Susan Schwartz, Andrew Fisher and Slawek Tulaczyk, University of California-Santa Cruz, Award No. 1043784 ; and Alberto Behar, Arizona State University, Award No. 1142123 . |