The Glacier-Climate Interaction Over the Tibetan Plateau and Its Surroundings During the Last Glacial Maximum

Glacier growth affects the local climate, and in turn, can either promote or prohibit its own growth. Such feedback has not been considered in modeling the glaciers of the Tibetan Plateau and its surroundings (TPS) during the Last Glacial Maximum (LGM; & SIM;28-23 ka). We find that the volume/area of the glaciers simulated by a coupled glacier-climate model is 20%/10% less than that by a standalone glacier model forced with fixed climate fields; glaciers advance toward their western rims and yet decrease in the interior of TPS. Such changes in spatial patterns improve model-data comparison. Moreover, the expansion of glaciers warms the winter surface temperature of the eastern TPS and decreases precipitation almost everywhere. These effects are primarily due to the added surface elevation, which blocks the water vapor brought by westerlies and south-westerlies, reducing precipitation and increasing surface temperatures to the east and northeast of the newly grown glaciers.