GISP2 D ice core
This ice core was drilled in 1989-1993 by The Greenland Ice Sheet Project 2 (GISP2). GISP2 recovered a 3053.44-m-deep ice core that penetrated 1.5 m into the underlying bedrock.
ORIGINATOR (CONTRIBUTORS): Mayewski, P.A.; Meeker, L.D.; Twickler, M.S.; Whitlow, S.I.; Yang, Q.; Lyons, W.B.; Prentice, M.
The Greenland Ice Sheet Project 2 glaciochemical series (sodium, potassium, ammonium, calcium, magnesium, sulfate, nitrate, and chloride) provides a unique view of the chemistry of the atmosphere and the history of atmospheric circulation over both the high latitudes and mid-low latitudes of the northern hemisphere. Interpretation of this record reveals a diverse array of environmental signatures that include the documentation of anthropogenically derived pollutants, volcanic and biomass burning events, storminess over marine surfaces, continental aridity and biogenic source strength plus information related to the controls on both high- and low-frequency climate events of the last 110,000 years. Climate forcings investigated include changes in insolation of the order of the major orbital cycles that control the long-term behavior of atmospheric circulation patterns through changes in ice volume (sea level), events such as the Heinrich events (massive discharges of icebergs first identified in t he marine record) that are found to operate on a 6100-year cycle due largely to the lagged response of ice sheets to changes in insolation and consequent glacier dynamics, and rapid climate change events (massive reorganizations of atmospheric circulation) that are demonstrated to operate on 1450-year cycles. Changes in insolation and associated positive feedbacks related to ice sheets may assist in explaining favorable time periods and controls on the amplitude of massive rapid climate change events. Explanation for the exact timing and global synchroneity of these events is, however, more complicated. Preliminary evidence points to possible solar variability-climate associations for these events and perhaps others that are embedded in our ice-core-derived atmospheric circulation records.
REFERENCES:
Mayewski, P.A., L.D. Meeker, M.S. Twickler, S.I. Whitlow, Q. Yang, W.B. Lyons, and M. Prentice. 1997. Major features and forcing of high-latitude northern hemisphere atmospheric circulation using a 110,000-year-long glaciochemical series. Journal of Geophysical Research 102:26345-26366. doi: 10.1029/96JC03365
Taylor, K.C., P.A. Mayewski, M.S. Twickler, and S.I. Whitlow. 1996. Biomass burning recorded in the GISP2 ice core: A record from eastern Canada? The Holocene 6(1):1-6.
Yang, Q., P.A. Mayewski, S.I. Whitlow, M.S. Twickler, M.C. Morrison, R.W. Talbot, J.E. Dibb, and E. Linder. 1995. Global perspective of nitrate flux in ice cores. Journal of Geophysical Research 100:5113-5121.
Mayewski, P.A., W.B. Lyons, M.J. Spencer, M.S. Twickler, C.F. Buck, and S.I. Whitlow. 1990. An ice core record of atmospheric response to anthropogenic sulphate and nitrate. Nature 346:554-556.