A New Mt. Logan Ice Core Record - Change in Climate and Chemistry of the Atmosphere for the North Pacific

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ABSTRACTOPP-0240878MayewskiMt. Logan, in the St. Elias Range, southeast Alaska, offers a unique opportunity for monitoring climate change and change in the atmospheric chemistry of the Gulf of Alaska and the North Pacific. In 1980, a 103-meter (M) ice core was recovered from Mt. Logan which spanned AD 1689-1980. It revealed well-defined annual layers, calibrated through the identification of radioactive bomb and volcanic horizons, allowing continuous, sub-seasonal sampling for stable isotopes and ion chemistry. The -29 degree C mean annual temperature at the site assures that the soluble, insoluble, and isotopic components of the core are well preserved. In 2001 and 2002, a new ice core to bedrock (190 M) was recovered from the Prospector-Russel Col area of Mt. Logan by the Geological Survey of Canada. Based on known accumulation rates and preliminary ice flow modeling, the new ice core record may span the entire Holocene and possibly into the Late Glacial. The Principal Investigators will develop and interpret detailed time series over the last 1000-2000 years, including multi-annual to decadal, through the Holocene and perhaps into the Late Glacial for major ions, stable isotopes, trace elements, and tephra utilizing state-of-the-art technology. Intellectual Merit: Interpretations resulting from this research will invoke calibrations between ice core measurements and instrumental series of sea level pressure and temperature first defined by associations found utilizing the 1980 Mt. Logan core. These interpretations will be enhanced by state-of-the-art environmental statistics, comparison with two cores developed by collaborators working at lower elevations in the same region (King Col and Eclipse Icefield), and comparison with other paleoclimate records from the North Pacific, as well as a global array of Holocene records. The highly detailed understanding of the different controls on the upwind side of the United States and Canada, developed from the new Mt. Logan record, should contribute to understanding future change in climate. This research will contribute directly to the understanding of: 1) recent North Pacific climate variability; 2) Northern Hemisphere to global Holocene climate variability; and 3) change in the chemistry of the atmosphere.Broader Impacts: This activity builds on two decades of ice core research which focuses on understanding natural climate variability in regions that record change in major atmospheric circulation patterns and change in the chemistry of the atmosphere. This project will provide support for the activities of two young faculty members (Kreutz and Kurbatov), full support for a Ph.D. student, partial support for several undergraduate/graduate students to participate in laboratory, data interpretation, and publication activities, and a request for instrumentation to enhance University of Maine ice core capabilities and efficiency. All data and interpretations will be shared in accordance with NSF policies.