Evidence for an early Holocene climatic optimum in the Antarctic deep ice-core record

This paper is focused on the Dome C and Vostok cores and on a new 850-m long ice core drilled out at Komsomolskaia by the Soviet Antarctic Expeditions in an attempt to clarify stable isotope content in terms of air temperature variations. These three sites are located in East Antarctica on the Antarctic plateau, in a region essentially undisturbed by ice-flow conditions, so that their detailed intercomparison may allow the identification of the climatically significant isotopic signal. Results compare well with the proximal records of Southern Hemisphere high latitudes, and support the existence of a warmer ``climatic optimum'' between 10 and 6 ka y BP. Maximum temperatures are reached just at the end of the last deglaciation, which confirms previous observations at high latitudes, in contrast with later dates for the Atlantic and hypsithermal optima in Europe and North America.