Ice Core Drilling in West Antarctica
What Are They Doing?
Using a large hollow drill, the WAIS Divide Ice Core Drilling team collected a 3,500-meter-long ice core, or sample of ice, from the West Antarctic Ice Sheet. Because of the weight of the overlying snowpack, snow that falls and accumulates on ice sheets re-crystallizes and forms annual layers over time. The ice core recovered during the project had annual resolution, or distinct yearly markings, for the past 40,000 years!
In ice sheets, the compression of snow traps small bubbles of air in the layers of ice. By measuring concentrations of greenhouse gasses and non-greenhouse gasses and their isotopes trapped within bubbles in the ice, the team developed climate records dating back to 100,000 years before present.
This ice core provided the first Southern Hemisphere climate and greenhouse gas records of comparable time, resolution, and duration to ice cores previously recovered in Greenland. The ice core enabled scientists to make detailed comparisons of greenhouse gas concentrations and environmental conditions between the Northern and Southern hemispheres with a greater level of detail than previously possible. The biology of the ice collected was also investigated.
Learn more about this process here