9402512 Landsberger This award supports dissertation-related research in Western Europe by a PhD student of Dr. Sheldon Landsberger from the University of Illinois at Urbana-Champaign. The graduate student, Mr. Steven Biegalski, will carry out atmospheric chemistry research at the RISO National Laboratory in Roskilde, Denmark. Dr. Landsberger and Mr. Biegalski are actively involved in research using source-receptor models to characterize the airborne pollutants in the Arctic and also to study the influence that halogens have on the destruction of ozone. Dr. Landsberger has received funding from Denmark to visit and collaborate with Dr. K. Heydorn and Dr. Kare Kemp of the Neils Bohr Institute. They are directing a Danish project to develop receptor models based on analyses of Arctic aerosols. Funding from the Western Europe Program of NSF will enable Mr. Biegalski to accompany Dr. Landsberger and to stay for two two-month periods to carry out research that will contribute to his dissertation. Participation in the ongoing research at RISO National Laboratory will give Mr. Biegalski access to field samples and specialized equipment and procedures not available to him at the University of Illinois. These will give him further insights into the role that the long range transport of atmospheric aerosols, particularly trace elements, play in global change. He will also gain experience in international collaboration at an early stage of his research career, and establish solid professional contacts with a leading atmospheric chemistry research group and its network of European collaborators. ***