HR: 08:00h
AN: PP11C-01 INVITED     [Abstracts]
TI: What can the ice core record tell us about high frequency climate changes?
AU: * Wolff, E W
EM: ewwo@bas.ac.uk
AF: British Antarctic Survey, High Cross, Madingley Road, Cambridge, CB3 0ET United Kingdom
AB: Ice cores show climate change on all frequencies from annual up to Milankovich frequencies, and the record now extends back to 800 kyr (but with much less time resolution in the longest records). In this paper, I will briefly review the different periods that can be observed in ice cores. The new European Project for Ice Coring in Antarctica (EPICA) Dome C core shows a clear shift in the pattern of climate about 400,000 years ago, with much warmer interglacials from MIS11 to the Holocene than were observed in MIS19 to 13. The record also shows the familiar 100 kyr cycles that dominate late Pleistocene climate. Within the last glacial period, we are all familiar with the millennial scale cycles (Dansgaard-Oeschger events) observed in Greenland cores, and we have the opportunity to test whether these are common to earlier glacials by looking for their subdued Antarctic counterparts, and for their accompanying methane excursions in the Antarctic records. It is harder to identify clearly millennial scale cycles in the Holocene, but the new EPICA core gives us a wide range of interglacials to investigate further. Finally, some ice core indicators in short, high resolution records may be able to show the persistence of very short period fluctuations such as ENSO, and I will briefly discuss the prospects for this. All of these frequencies are of course high frequency in the geological context! The paper will draw on work by many ice core colleagues
DE: 3344 Paleoclimatology
DE: 1620 Climate dynamics (3309)
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2004 AGU Fall Meeting