New Mexico Geological Society Annual Spring Meeting — Abstracts

New Mexico communities and economies rely on snow-fed surface and groundwater resources. According to recent reports, climate change is projected to influence both snow quantity and seasonality this century, with predominantly negative implications for New Mexico. Therefore, understanding the magnitude and uncertainty of these projections is essential for designing water management strategies. Increasingly, Earth System Models (ESM), which couple the atmosphere with sophisticated representations of the land surface and ocean, are used to predict future changes in global snow variability. However, the skill of ESMs in simulating snow regionally is still poorly characterized. Here we evaluate the skill of the NOAA Geophysical Fluid Dynamics Laboratory (GFDL) ESMv4.1 in simulating snowpack across the Western US (WUS). Our analysis focuses on contrasting model performance in the southwest with other parts of the WUS in order to identify the source of model biases and limitations that might impact southwestern snow projections. Large scale model evaluation utilizes snow products derived from both satellite observations and historical reconstructions of snow water equivalent. Additionally, we isolate the nature of any observed regional model bias by running the land component of the ESM individually at a diverse selection of sites using available in situ forcing and evaluation data. Once model behavior is adequately characterized, future predictions for the southwest and NM made by the GFDL ESM can be interpreted with less uncertainty.