New Antarctic Ice Core to Provide Clearest Climate Record Yet
Scientists on the West Antarctic Ice Sheet have closed out the inaugural season of an unprecedented, multiyear effort to retrieve the largest, most detailed record of greenhouse gases in Earth’s atmosphere over the last 100,000 years.
After three weeks of round-the-clock drilling for the National Science Foundation’s (NSF) West Antarctic Ice Sheet Divide (WAIS Divide) Ice Core Project–730 miles north of the South Pole, with summer waning and temperatures peaking at a balmy 5 degrees Fahrenheit–scientists, engineers and technicians from multiple U.S. institutions produced a 2,132-foot ice core- -the first section of what is hoped to be a 11,300-foot column of ice (just over two-miles long) detailing 100,000 years of Earth’s climate history, including a precise year-by-year record of the last 40,000 years.
The dust, chemicals and air trapped in the ice core will provide critical information for scientists working to predict the extent to which human activity will alter Earth’s climate, according to the chief scientist for the project, Kendrick Taylor of the Desert Research Institute (DRI) of the Nevada System of Higher Education. DRI, along with the University of New Hampshire, operate the Science Coordination Office for the WAIS Divide Project.
WAIS Divide, named for the high-elevation region that demarcates movement of the vast ice sheet in opposite directions, is the best spot on the planet to recover ancient ice containing trapped air bubbles–samples of the Earth’s atmosphere from the present to as far back as 100,000 years ago.
While other ice cores have been used to develop longer records of Earth’s atmosphere, the record from WAIS Divide will allow a more detailed study of the interaction of previous increases in greenhouse gases and climate change. This information will improve computer models that are used to predict how the current, unprecedented high levels of greenhouse gases in the atmosphere caused by human activity will influence future climate.
The WAIS Divide core is also the Southern Hemisphere equivalent of a series of ice cores drilled in Greenland beginning in 1989, and will provide the best opportunity for scientists to determine if global-scale climate changes that occurred before human activity started to influence climate were initiated in the Arctic, the tropics, or Antarctica.
“We are very excited to work with ancient ice that fell as snow as long as 100,000 years ago,” Taylor said. “We read the ice like other people might ready a stack of old weather reports.”
The WAIS project took more than 15 years of planning and preparation, including extensive airborne reconnaissance and ground-based geophysical research, to pinpoint the less-than-one-square-mile space on the 360,000 square mile ice sheet that scientists believe will provide the clearest climate record for the last 100,000 years.
For the project, Ice Coring and Drilling Services of the University of Wisconsin-Madison built a state-of-the-art deep ice-coring drill, which is more like a piece of scientific equipment than a conventional water or oil drill. The National Ice Core Laboratory in Denver designed the core handling system. Raytheon Polar Services Corporation provides the logistical support. Funding is provided by the NSF Office of Polar Programs-U.S. Antarctic Program.
With only 40 days a year when the weather is warm enough for drilling, it is expected to take until January 2010 to compete the fieldwork. The core will be archived at the National Ice Core Laboratory, which is run by the U.S. Geological Survey with funding from NSF.
