Abstract

Mountain snowpack globally is a natural water tower, which stores winter precipitation and releases it in spring, and is one of the major sources of water. Winter precipitation pattern and radiative impacts of light absorbing aerosols deposition on snow can change the amount and timing of snowmelt, which not only has implications on water security but also food security, hydropower generation, regional ecology and hazards. However, quantifying mountain snowpack through observation, even with the use of remote sensing, is challenging due to the remoteness and colocation with cloudy regions.

Here, we present an analysis of a 36-year simulation with the new Geophysical Fluid Dynamics Laboratory (GFDL) atmospheric model (AM4) coupled to a land surface model (LM4) with a 50 km horizontal resolution (referred to as AM4 -LM4) and using fixed observed sea surface temperatures. The spatial distribution, seasonal variability and trends of snow precipitation and deposition of aerosols, such as mineral dust and black carbon, over major mountain ranges with a particular emphasis on High Mountain Asia will be discussed. We then explore the impacts of aerosols deposition on snow albedo and snowmelt in High Mountain Asia.