Do Greenland Ice Cores Reflect NW European Interglacial Climate Variations?

Abstract

The climatic evolution during the Eemian and the Holocene in western Europe is compared with the sea-surface conditions in the Norwegian Sea and with the oxygen-isotope-derived paleotemperature signal in the GRIP and Renland ice cores from Greenland. The records show a warm phase (ca. 3000 yr long) early in the Eemian (substage 5e). This suggests that the Greenland ice sheet, in general, recorded the climate in the region during this time. Rapid fluctuations during late stage 6 and late substage 5e in the GRIP ice core apparently are not recorded in the climatic proxies from western Europe and the Norwegian Sea. This may be due to low resolution in the terrestrial and marine records and/or long response time of the biotic changes. The early Holocene climatic optimum recorded in the terrestrial and marine records in the Norwegian Sea-NW European region is not found in the Summit (GRIP and GISP2) ice cores. However, this warm phase is recorded in the Renland ice core. Due to the proximity of Renland to the Norwegian Sea, this area is probably more influenced by changes in polar front positions which may partly explain this discrepancy. A reduction in the elevation at Summit during the Holocene may, however, be just as important. The high-amplitude shifts during substage 5e in the GRIP core could be due to Atlantic water oscillating closer to, and also reaching, the coast of East Greenland. During the Holocene, Atlantic water was generally located farther east in the Norwegian Sea than during the Eemian.