Comparison of St. Elias Ice Core Accumulation Records and Their Relationships to Climate Indices
Abstract
Recently recovered ice cores from the St Elias Mountains (Yukon) spanning an elevation range of three (Eclipse Icefield) to more than five kilometers (Mount Logan) offer a unique three-dimensional view of paleoclimate and environmental change in the North Pacific region. The record of net accumulation as deduced from the reconstruction of observed annual layer thicknesses in these cores offers a direct view of moisture flux at various altitudes in the St. Elias. However, a potentially large uncertainty in the representativeness of ice core accumulation records exists due to spatial variability in snow accumulation rates. The availability of multiple cores allows us to address this issue. Accumulation records from Eclipse (three cores) are highly reproducible with 78% of the signal shared between the three cores. The proportion of shared signal between accumulation records from the Logan plateau (Prospector-Russell Col and Northwest Col) is lower (52%). In this work we will compare the Eclipse and Logan accumulation records to each other to understand the spatial variability in net accumulation over time at different altitudes. The possible influence of dating errors on these results will be explored using leads and lags of 1-2 years. We also compare our accumulation records to indices of atmospheric circulation (e.g., strength of the Aleutian Low, the Pacific Decadal Oscillation, the El-Nino Southern Oscillation, Arctic Oscillation) to quantify relationships between snow accumulation and large-scale atmospheric circulation features on time-scales of variability ranging from years to centuries.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2006
- Bibcode:
- 2006AGUFMPP54A..05Y
- Keywords:
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- 0724 Ice cores (4932);
- 1637 Regional climate change;
- 3344 Paleoclimatology (0473;
- 4900);
- 3354 Precipitation (1854);
- 9315 Arctic region (0718;
- 4207)