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Considering the sea-level constraints and the detailed records of regional climate change available from the ice cores, the EPILOG group reached a consensus that a preferred LGM chronozone can be defined as the interval between 19,000 and 23,000 cal-yrBP (i.e., 16,100-19,500 14C-yr BP). This 4000-yr time window, centered on 21,000 cal-yr BP, encompasses the center of the LGM event defined previously by CLIMAP (1976, 1981), and is long enough to allow the inclusion of much existing paleoclimatic data in a new synthesis. It is coeval with the lowest stand of sea level (Yokoyama et al., 2000), avoids all known Heinrich Events in the North Atlantic region, and excludes most of Dansgaard-Oeschger climate event D/O-2, as dated in the GISP2 ice core and in the GRIP core (with the chronology of Hammer et al., 1997). The time window avoids the major deglacial warming in Antarctica, although it may include the beginning of the earliest warm events in the south (Blunier et al., 1998; Bender et al., 1999). This issue will require strengthening of ice core dating to resolve the discrepancies among the published studies.
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