Glacier‐Climate Feedbacks Modulate Last Glacial Maximum Dust Cycle Over the Third Pole

Abstract

Geological records indicate only a modest Last Glacial Maximum (LGM) increase in dust deposition over the Third Pole (TP), in contrast to the order‐of‐magnitude rise at high latitudes. Existing climate simulations, which generally prescribe present‐day or no TP glaciers, have struggled to reproduce this muted response. Here, we two‐way couple a climate model with a glacier model to simulate the LGM dust cycle over the TP. Glacier expansion suppresses local emissions by capping major source areas and reorganizing hydroclimate and circulation. These feedbacks also reshape transport and deposition, yielding an LGM‐to‐modern dust ratio at Guliya that agrees with the ice‐core record, whereas an uncoupled experiment substantially overestimates the increase. Our results identify glaciers as active regulators of the high‐mountain dust cycle, and provide a physical basis for interpreting paleodust records and projecting future dust and cryosphere change.