This award is in support of the second Greenland Ice Sheet Project (GISP 2). The objective of this project is to assist in the climatic interpretation of the GISP 2 core by measuring its electrical conductivity as a function of depth. This will allow a time-depth relationship to be developed for the core, and permit sampling by other investigators to be more efficient because of advance knowledge of the core's gross chemistry. In addition, the existence of long- term climatic trends and oscillation will be investigated. Results from the first year of the GISP 2 program show that a vertical resolution of 3 mm is possible; this will permit resolution of annual layers to an age of approximately 30,000 B.P. In ice older than 30,000 years, annual resolution will be lost but longer term events will be detectable. Preliminary results from the 1989 GISP 2 field season demonstrate the effectiveness of the method. The results of this proposal, combined with the other aspects of the GISP 2 program, will enhance our understanding of the earth's paleoclimate and ongoing climatic processes.
