Glaciers and climate in Pacific Far NE Russia during the Last Glacial Maximum

Abstract

AbstractA combined geomorphological–physical model approach is used to generate three‐dimensional reconstructions of glaciers in Pacific Far NE Russia during the global Last glacial Maximum (gLGM). The horizontal dimensions of these ice masses are delineated by moraines, their surface elevations are estimated using an iterative flowline model and temporal constraints upon their margins are derived from published age estimates. The equilibrium line altitudes (ELAs) of these ice masses are estimated, and gLGM climate is reconstructed using a simple degree–day melt model. The results indicate that, during the gLGM, ice masses occupying the Pekulney, Kankaren and Sredinny mountains of Pacific Far NE Russia were of valley glacier and ice field type. These glaciers were between 7 and 80 km in length, and were considerably less extensive than during pre‐LGM phases of advance. gLGM ice masses in these regions had ELAs of between 575 ± 22 m and 1035 ± 41 m (above sea level) – corresponding to an ELA depression of 350–740 m, relative to present. Data indicate that, in the Pekulney Mountains, this ELA depression occurred because of a 6.4°C reduction in mean July temperature, and 200 mm a−1 reduction in precipitation, relative to present. Thus reconstructions support a restricted view of gLGM glaciation in Pacific Far NE Russia and indicate that the region's aridity precluded the development of large continental ice sheets. Copyright © 2011 John Wiley & Sons, Ltd.