HR: 1340h
AN: PP33C-1583    [Abstracts]
TI: The Flickering Switch of Late Pleistocene Climate Change: Revisited
AU: * Barker, S
EM: sbarker@ldeo.columbia.edu
AF: Lamont-Doherty Earth Observatory, PO Box 1000, 61 Route 9W , Palisades, NY 10964 United States
AB: Extremely rapid fluctuations observed in records of electrical conductivity measurements (ECM) from Greenland ice-cores provoked the idea that the climate system may be capable of flickering between two states during rapid climate transitions. Here it is shown that in general, the flickers seen in ECM records probably reflect the highly non-linear response of electrical conductivity as ice approaches acid / base neutrality, rather than significant changes in the climate system. High frequency, relatively low amplitude changes in chemistry, superimposed upon the smoother changes typical of climate transitions would be capable of producing the observed characteristics of ECM records. It must be stated that this result does not detract from the observation of extremely rapid changes in, for example, ice core chemistry and isotopes, which clearly demonstrate that Earth's climate is capable of very rapid and major reorganisations.
DE: 0724 Ice cores (4932)
DE: 1605 Abrupt/rapid climate change (4901, 8408)
DE: 3305 Climate change and variability (1616, 1635, 3309, 4215, 4513)
DE: 3344 Paleoclimatology (0473, 4900)
SC: Paleoceanography and Paleoclimatology [PP]
MN: Fall Meeting 2005