The Role of Atmospheric Dynamics and Climate Change on the Possible Fate of Glaciers in the Karakoram

Abstract

Abstract High-resolution regional climate simulations for the Karakoram Mountain range in the greater Himalayas have been performed to investigate the atmospheric dynamics of this region, and their role in the Karakoram’s snowfall accumulation and possible glacial evolution through the next century. It has been found through a combination of field measurements and satellite observations that glaciers in this region appear to be reacting differently to contemporary climate change than those in other regions. This region has exhibited a relatively large number of either static or advancing glaciers while other glaciers in the central and eastern Himalayas, as well as around the world, are nearly all retreating. The amount of precipitation received in the Karakoram region depends on the interplay between two climate systems: the westerly winds flowing over the Mediterranean and Caspian Seas, and the South Asian monsoon winds (also referred to as the Indian monsoon) flowing over the Indian Ocean. This study extends the modeling time frame by performing time-slice calculations for the Karakoram region through the twenty-first century. Despite regionwide simulated temperature changes, the highly elevated regions of the Karakoram Mountain range experience positive climatic mass balance until the end of the modeling time period. This result arises from a strong positive correlation between climatic mass balance and simulated increases in regional precipitation, which outweighs the negative correlation between climatic mass balance and simulated increases in temperature. Also, the extreme elevations within the Karakoram allow regional alpine glaciers to benefit from a strong elevation-dependent signal simulated in net snowfall accumulation, and hence climatic mass balance.