Indiana University Purdue University Indianapolis

School of Science Researcher Looking to the Past to Improve Climate Change Models for the Future; Uses Prestigious Fellowship to Work with Colleague at Columbia University

Release Date: 
Feb 8 2010

 

Dr. Kathy Licht, Associate Professor of Earth Sciences in the School of Science at IUPUI, is working at Columbia University under a prestigious Marie Tharp Fellowship to expand understanding of how climate change may impact the Antarctic by looking thousands of years into the past.

The ADVANCE Program of the Earth Institute at Columbia University awards several Marie Tharp Fellowships each year to promising women scientists. The fellowship program is designed to help women advance into the upper ranks of academia, positions that have traditionally been filled with men.

The fellowship is named after Marie Tharp, who was the first to map details of the ocean floor on a global scale. Tharp published the pivotal interpretation of mid-ocean ridges that was crucial to the eventual acceptance of the theories of plate tectonics and continental drift.

According to Licht, reliable predictions of the West Antarctic ice sheet's future response to changing climate and rising sea levels depend, to a large extent, on improving knowledge and understanding of its ice dynamics during the last glacial maximum (~18,000 yrs ago).

Sediments from the Ross Sea, Antarctica contain a detailed physical record that can be used to reconstruct the glacial history of the region and therefore test the accuracy of theoretical ice sheet models required to predict future sea level rise.

Licht, who led scientific expeditions to the Antarctic in 2005 and 2006, brought home samples of sediment that she and Sydney Hemming, an associate professor in the Department of Earth and Environmental Sciences at Columbia University, are now analyzing.
“She has equipment I don’t have and I have samples she doesn’t have, so it seems like a good match” Licht said.

The data from Licht’s on land samples from the 2006 expedition will be compared with sediment samples Hemming has collected from the polar region’s ocean floor.

The analysis of the two sets of sediment samples will provide insights into the stability of the ice sheets, Licht said. “For example, if ice in one area of the Antarctic ice sheet became unstable, it likely broke up into many icebergs. Those icebergs drifted around in the southern ocean, dropping pieces of rock they were carrying.”

Hemming and Licht are trying to link sediment collected from the ocean floor back to land to identify from which parts of the ice sheet they came.

Since the locations of where Licht’s samples are known, it will be possible to link with greater confidence Hemming’s samples from the sea floor back to the continent so it can determined which parts of the ice sheet collapsed in the past.

“We are looking back at sediment from the last and previous ice ages to see what parts of the ice sheet break down and which parts are most susceptible to global warming from the historical data we are collecting,” Licht said. “That will help the climate change modelers see what targets they need to hit if they are going to model the past. If that can be done, then there is more confidence in the projections going forward.”