Quaternary International, Vol. 10--12,pp. 107-122, 1991. 1040--6182191 $0.00 + .50 Printed in Great Britain. All rights reserved. © 1992 INQUA/PergamonPress Ltd ISOTOPE STAGE 5 (130-74 ka) IN GREENLAND, A REVIEW Svend Funder,* Christian Hjortt and Michael Kelly$ *Geological Museum, Ostervoldgade 5-7, DK-1350 Copenhagen K, Denmark t Department of Quaternary Geology, Universityof Lund, SOlvegatan12, S-22362 Lund, Sweden SDepartment of Environmental Science, Universityof Lancaster, LA1 4YQ Lancaster, U.K. Marine and glacigene deposits, dated with varying degrees of certainty to isotope stage 5 (130-74 ka) are exposed in coastal cliffs in 18 areas and localities in northern and eastern Greenland. Dating methods include thermoluminescence (TL), U-Th methods and correlation with the deep sea record. Amino-acid parameters are used for correlation between localities. Deposits from the last interglaciation (isotope substage 5e) are rare and have been found only at three localities in both West and East Greenland. Their mollusc and foraminifer faunas indicate more vigorous sea surface circulation and sea surface temperatures some degrees higher than known from the Holocene. During this warm period ice sheet growth began. In Northwest Greenland the ice sheet reached its maximum for the last ice age during the succeeding phase, provisionally correlated with isotope substage 5d. This was followed by a new warm period with increased influx of warm subarctic water, and high summer temperatures on land, provisionally correlated with isotope substage 5a. In East Greenland the observations indicate a more complex ice sheet history. The record from Greenland is very similar to that obtained in adjacent coastal areas of the high Arctic implying that the rapid shifts from warm to cold during isotope stage 5 were especially conducive to the formation of the embryonic North American and Scandinavian ice sheets at high northern latitudes, probably because the pulses of warm water were required to advect sufficient moisture into these areas to allow the growth of continental ice sheets. INTRODUCTION Stage 5 in the global isotope stratigraphy covers the last interglaciation (isotope substage 5e) and the beginning of the last ice age, and is characterised by its succession of rapid changes in global ice volume (Schackleton, 1987). In high arctic areas raised marine sediments from this period now seem to be widespread, showing that these areas experienced isostatic subsi- dence and ice sheet growth. The raised deposits therefore contain important information on the transi- tion from interglacial to glacial conditions, and the inception of the large continental ice sheets. This report gives a review of published observations on these deposits in Greenland which, from different criteria and with varying degrees of certainty, have been referred to as isotope stage 5. The sediments are exposed in coastal cliffs along fjords and at the outer coasts of the Greenland ice-free land fringe, especially in the least accessible northern and eastern parts of the country, where glacial erosion has been least destruc- tive (Fig. 1). The descriptions concentrate on dating and climatic/ oceanographic implications. These results have emerged from geological studies during the last twenty years, and are closely related to the development of new methods for dating and correlation, such as thermoluminescence dating, amino-acid analyses and micropaleontological work on marine faunas. The resultant local stratigraphies produced for the four key areas (loc. 3, 5, 13 and 18) are shown and correlated in Table 1. Previous reviews have been published by Weidick (1976), Funder (1984, 1989) and Kelly (1985, 1986). Since then important new evidence has been published from the Thule area, providing more reliable dating and a re-evaluation of older work (NORDQUA- participants, 1989; Funder, 1990a). ~lso sites in East Greenland which have only been superficially referred to in previous publications, are mentioned. In spite of its speculative nature the so-called 'refugium-debate,' about the possible ice age survival of plants is briefly reviewed, because of its possible relevance for charac- terising isotope stage 5 terrestrial environments which are otherwise very little known. The chronostratigraphical terminology follows Man- gerud (1989) and dating of the marine isotope stages is from the 'short SPECMAP curve' (Martinson et al., 1987). Thus, the last interglaciation is considered to be equivalent to the Eemian = Sangamonian = isotope substage 5e = 130-122 ka and the last ice age = Weichselian = Wisconsinan = isotope substage 5d to isotope stage 1 = 120-12 ka. Currently, studies on the climatic and glacial history of the last interglacial/glacial cycle are taking place both in Northwest and East Greenland.* In a few years time these results will provide a more detailed knowledge of the last interglacial/glacial cycle in the North Atlantic *The 'Thule-89 Project,' describing new evidence from the Thule area, and islands between Greenland and Canada, currently in the work-up phase, and the 'PONAM-project,' a major European Science Foundation inspired effort to elucidate climatic change and ice sheet response around and in the Norwegian and Greenland Seas, begun in 1990. 107