A "critical" climatic evaluation of last interglacial (MIS 5e) records from the Norwegian Sea

Sediment cores from the Norwegian Sea were studied to evaluate interglacial climate conditions of the marine isotope stage 5e (MIS 5e). Using planktic forminiferal assemblages as the core method, a detailed picture of the evolution of surface water conditions was derived. According to our age model, a step-like deglaciation of the Saalian ice sheets is noted between ca. 135 and 124.5 Kya, but the deglaciation shows little response with regard to surface ocean warming. From then on, the rapidly increasing abundance of subpolar forminifers, concomitant with decreasing iceberg indicators, provides evidence for the development of interglacial conditions sensu stricto (5e-ss), a period that lasted for about 9 Ky. As interpreted from the foraminiferal records, and supported by the other proxies, this interval of 5e-ss was in two parts: showing an early warm phase, but with a fresher, i.e., lower salinity, water mass, and a subsequent cooling phase that lasted until ca. 118.5 Kya. After this time, the climatic optimum with the most intense advection of Atlantic surface water masses occurred until ca. 116 Kya. A rapid transition with two notable climatic perturbations is observed subsequently during the glacial inception. Overall, the peak warmth of the last interglacial period occurred relatively late after deglaciation, and at no time did it reach the high warmth level of the early Holocene. This finding must be considered when using the last interglacial situation as an analogue model for enhanced meridional transfer of ocean heat to the Arctic, with the prospect of a future warmer climate

IODP expedition 310 reconstructs sea level, climatic, and environmental changes in the South Pacific during the last deglaciation

The timing and course of the last deglaciation (19,000–6,000 years BP) are essential components for understanding　the dynamics of large ice sheets (Lindstrom and MacAyeal,　1993) and their effects on Earth’s isostasy (Nakada and　Lambeck, 1989; Lambeck, 1993; Peltier, 1994), as well as the　complex relationship between freshwater fluxes to the ocean,　thermohaline circulation, and, hence, global climate during　the Late Pleistocene and the Holocene. Moreover, the lastdeglaciation is generally seen as a possible analogue for the　environmental changes and increased sea level that Earth　may experience because of the greenhouse effect, related　thermal expansion of oceans, and the melting of polar ice　sheets