Glacial history and paleoceanographic changes of the western Arctic Ocean (Mendeleev Ridge) using beryllium isotopes

Abstract

Beryllium isotopes have been used as a proxy to understand paleoclimate signals which correspond well with oxygen isotope stages. Previous publications related with this aspect are well established in the science community related to paleoclimate change for both marine and lake environments [Aldahan et al., 1997]. In general, for warmer period, both the concentrations of beryllium isotopes were relatively higher than during colder period. Our recent investigation for the East Sea, Korea also shows this trend clearly although the characteristics of marine environmental setting and sediment accumulation are still revealed through the pattern of these isotopes as a proxy representing the regional climatic environment [Kim and Nam, 2010]. A new investigation of paleoclimate and environmental changes using beryllium isotopes for the Mendeleev Ridge of the western Arctic Ocean was accomplished using the 39 cm-long box core sediment (PS72/396-3 GKG) which was recovered during the Polarstern ARK23/3 Expedition in 2008. The age of core PS72/396-3 seems to be back to MIS 5.1 based on lithostratigarphy (well known brown- gray colour and pink layers), AMS 14C ages and oxygen and carbon isotopes of planktonic foraminifer N. pachyderma sin.