Investigation of the Impacts of Spatial Variability of Soil Moisture on Convective Precipitation in the Central Plains

Altering the spatial and temporal variability of soil moisture and vegetative cover can potentially lead to significant impacts on local weather and climate through feedbacks in surface energy balance partitioning, water dynamics, and precipitation. In order to examine the impacts of spatial heterogeneity of soil moisture on convective precipitation, a suite of 15 simulations were conducted using the Advanced Regional Prediction System (ARPS) mesoscale model with resolutions ranging from 1 km to 16 km. Model spin-up induces spatial variance in soil moisture via topographic redistribution. Following spin-up, we are able to examine how initial soil moisture and the associated spatial variance impact the surface energy balance and resulting feedbacks on convective precipitation as a function of spatial scale and downwind distance. To investigate these responses as a function of mean soil moisture, initial soil moisture conditions were varied from wilting point to field capacity for each resolution. Implications for the impact on local land-atmosphere interactions resulting from anthropogenic changes to land-surface cover and moisture availability via agricultural practices and irrigation will be discussed.