Drilling on the Edge
By CHRISTIAN ELLIOTT, Science.
Excerpt: The helicopter hovered overhead, whipping up snow. ...One trip down, 17 more to go, thought [Peter] Neff, a polar glaciologist at the University of Minnesota (UM) Twin Cities. ...Neff and his team would have just 10 days to drill ice cores on Canisteo, a peninsula on the west coast of Antarctica—and a blizzard was already looming. ...Scientists usually target sites deep in the continent’s interior, where the weather is calmer and they can spend years collecting kilometers-long ice cores that record hundreds of thousands of years of climate history. Neff needed just a couple hundred years of history, and he only needed to drill 150 meters deep to get it. But his chosen location was exceptionally remote and stormy. He was there because of ...the Pine Island and Thwaites glaciers, which jut into the Amundsen Sea as frozen shelves tens of kilometers wide. These glaciers act as corks in the bottle of the West Antarctic Ice Sheet, which ...stores enough water to raise sea level by 3 to 5 meters. Global warming is loosening the corks. Because Pine Island and Thwaites rest on bedrock that sits below sea level, incursions of warm seawater are melting their foundations, undermining them and speeding their flow. Around the end of the century, if global warming continues unabated, “we’ll see a big increase in the flow of ice delivery to the ocean and the pace of sea level rise: the beginning of a total collapse of the West Antarctic Ice Sheet,” says Ted Scambos, principal investigator for the International Thwaites Glacier Collaboration....