Abstract ATM-9808963 Mayeswki, Paul A. University of New Hampshire Title: Holocene Climate Variability With the successful completion of deep drilling at Summit Greenland there is now a well-dated, high resolution, multi-parameter record of climate change for the Northern Hemisphere that covers the last glacial cycle. The GISP2 record reveals evidence of rapid and dramatic change in climate. Recent examination of the Holocene portion of the Greenland record has demonstrated that, while relatively stable by comparison with glacial age climate, the Holocene contains subdued versions of glacial age millennial scale rapid climate change events. The Holocene record is characterized by significant annual to centennial scale variability plus significant and complex forcing and response histories. Understanding Holocene climate is essential to the differentiation of natural versus anthropogenic climate response and forcing and to any prediction of future climate. This award supports an investigation designed to refine and expand our knowledge of the Holocene GISP2 glaciochemical record and to utilize several other existing paleoclimate records (e.g., ice core, marine sediments) for comparison. The primary analytical emphasis is the production of ultra-high resolution major ion series (chloride, nitrate sulfate, calcium, magnesium, sodium, potassium and ammonium) and MSA. These represent >95% of the soluble ions in the atmosphere and can be used: (1) to develop environmental records (e.g., volcanic history, marine and continental biogenic source productivity); (2) in the reconstruction of atmospheric circulation systems and (3) to develop more precise dating of existing ice core records. This study will add a new dimension to the classic stable isotope-temperature reconstruction of climate by defining, through the examination of glaciochemical series, complementary measures of variability in atmospheric circulation.