Steven J. Ghan
Pacific Northwest National Laboratory
Editor in Chief of the Journal of Geophysical Research – Atmospheres
http://www.pnl.gov/atmospheric/staff/staff_info.asp?staff_num=5663
As the climate warms during this century more of the precipitation is expected to fall was rain rather than snow, reducing mountain snowpack in many regions of the world. Since snowmelt during spring and summer months is heavily relied on for irrigation of crops, the loss of this summertime water source is of concern to those engaged in agriculture. However, providing quantitative estimates of the impact of future warming on mountain snow is challenging because mountainous terrain is poorly resolved in global climate models. To deal with this challenge, I have developed and implemented a representation of the influence of subgrid topography on local climate in a global climate model. In this seminar I will describe this approach and demonstrate its performance in various mountainous regions of the world. I will then apply it to a future warming scenario out to year 2100, and show impacts of the warming on snowpack in those regions.