HR: 0830h
AN: OS21B-1123    [PDF]
TI: Multi-Century Greenland Ice Sheet Accumulation Variability and the North Atlantic Oscillation
AU: * Glueck, M F
EM: maryg@hwr.arizona.edu
AF: Department of Hydrology and Water Resources, University of Arizona, P.O. Box 210011, Tucson, AZ 85737 United States
AU: Bales, R C
EM: rbales@ucmerced.edu
AF: School of Engineering, University of California, Merced, P.O. Box 2039, Merced, CA 95344 United States
AB: The Greenland Ice Sheet is a unique natural recorder of climate variability in the North Atlantic region. However, limitations in data coverage have made it difficult to obtain an overall assessment of accumulation and accumulation-climate relationships across the Greenland Ice Sheet. We have investigated accumulation variability across the ice sheet and accumulation-climatic index (e.g., North Atlantic Oscillation) relationships using a recently compiled, comprehensive, high-quality set of annually dated multi-century Greenland ice sheet accumulation records. The series include primarily data from recent multi-century cores, records from Danish archives, and other historical coring efforts from across Greenland. The common period of record for the 35 multi-century series initially available is 1966-1781 (core dates range from 1998 to the past several millennia). Based on similarities evident in core-core comparisons, geographic location, and core-NAO relationships, we reduced the 35 initial accumulation series to 21 representative series. Core-core correlations between the final series indicate that when significant correlations exist, they tend to be strongest in the 1850-1950 period. However, in general, sliding correlation analysis indicates that correlation strength varies noticeably over time and between cores. Significant correlation is also apparent between the annual NAO and multiple accumulation series. Specifically, the highest significant NAO-accumulation correlations were obtained for Azores-Iceland NAO indices and accumulation series from central and northwest Greenland (r = -0.26 to -0.34). Based on statistical analysis of similarities in accumulation characteristics, the 21 series can also be clustered into regional groups and stacked to form eight composite regional series, six of which include at least 700 years of data (common period: 1244-1984). Results of our initial NAO-regional composite series analyses indicate that the west-central and northwestern regions are most strongly correlated with the annual instrumental NAO while the southern series shows only weak correlation with NAO.
DE: 1827 Glaciology (1863)
DE: 3309 Climatology (1620)
DE: 3344 Paleoclimatology
DE: 3349 Polar meteorology
DE: 4215 Climate and interannual variability (3309)
SC: Ocean Sciences [OS]
MN: 2003 Fall Meeting