US ITASE Research Summary

By Paul A. Mayewski

Compared to most areas on Earth the vast continent of Antarctica has been, except for the most recent decades, a minor focus of scientific exploration. Yet what is already known about Antarctica conclusively demonstrates that, despite its remote location, it plays a significant role in the global system. Assessing Antarctica's role in global change offers a major scientific challenge because of the vastness of the continent, variable climatic conditions (sea ice, snow accumulation rate, atmospheric circulation), and the influence of human activity on the environment of the region (ozone hole, long-traveled pollutants, research station signatures).

Under the international banners of the International Geosphere Biosphere Project (IGBP) and the Scientific Committee on Antarctic Research (SCAR), the International Trans-Antarctic Scientific Expedition (ITASE) was developed to meet this challenge. Under the national banner of the West Antarctic Ice Sheet (WAIS) initiative, multidisciplinary workshops were organized and attended by the U.S. scientific community to formulate the scientific questions and methodologies needed to undertake this challenge in West Antarctica resulting in US ITASE.

US ITASE is made up of six major research disciplines: meteorology, remote sensing, geophysics, ice coring, surface glaciology, and atmoshpheric chemistry.

The approach to our research and the challenge of assessing Antarctica's role in global change depends on the analysis and interpretation of the concentrations of various chemicals present in the ice. These qualities of the glaciochemical record, further clarified in the projects described to the right, will be used to address the following scientific questions:

1. What is the current rate of change in mass balance over West Antarctica?
2. What is the influence of major atmospheric circulation systems and oceanic circulation on the moisture flux over West Antarctica?
3. How does climate vary over West Antarctica on seasonal, inter annual, decadal and centennial scales, and what are the controls on this variability?
4. What is the frequency, magnitude and effect of any extreme climate events recorded in West Antarctica?
5. What is the impact of anthropogenic activity (e.g., ozone depletion, pollutants) on the climate and atmospheric chemistry of West Antarctica?
6. How much has biogeochemical cycling of sulfur and nitrogen, as recorded in West Antarctica, varied over the last 200+ years?