U.S.-France Cooperative Research: Nitrogen and Sulfur Cycles in Antarctica Inferred from Concentration and Isotopic Measurements

University Of California-San Diego, La Jolla CA

Investigators

Abstract

0128971 Thiemens This three-year award for US-France collaboration on biogeochemical studies in Antarctica involves Mark H. Thiemens and students at the University of California at San Diego and Michel Legrand and Robert Delmas of the Glaciology and Physical Environment Laboratory (CNRS, Grenoble, France). They will study atmospheric sulfur and nitrogen cycles in Antarctica using gas concentration and a combination of sulfur, nitrogen and oxygen isotopic measurements. Multi-isotope ratio measurement and integration of mass independent isotopic chemistry will be employed. Specifically, sulfur and nitrogen species at the French Antarctic station will be studied using gas concentration, aerosols, size distribution, and composition in addition to isotopic ratio measurements. Concentrated and isotopic measurements of ionic species trapped in the Vostok ice cores, currently in stored in France, also will be investigated. The US researchers bring to this collaboration expertise in ice analysis. This is complemented by French expertise in ice core chemistry and access to French Antarctic research facilities and special ice cores. Studies of Antarctic ice cores will advance understanding of the Antarctic atmosphere, ozone depletion, and the causes of climate transition. This award represents the US side of parallel proposals to the NSF and the CNRS. NSF will cover travel funds and living expenses for the US investigators and students. The CNRS will support visits by French researchers to the United States.