Physical Sciences and Mathematics Commons^™

Dynamical Precipitation Downscaling For Hydrologic Applications Using Wrf 4d-Var Data Assimilation: Implications For Gpm Era, Liao-Fan Lin, Ardeshir M. Ebtehaj, Rafael L. Bras, Alejandro N. Flores, Jingfeng Wang

Geosciences Faculty Publications and Presentations

The objective of this study is to develop a framework for dynamically downscaling spaceborne precipitation products using the Weather Research and Forecasting (WRF) Model with four-dimensional variational data assimilation (4D-Var). Numerical experiments have been conducted to 1) understand the sensitivity of precipitation downscaling through point-scale precipitation data assimilation and 2) investigate the impact of seasonality and associated changes in precipitation-generating mechanisms on the quality of spatiotemporal downscaling of precipitation. The point-scale experiment suggests that assimilating precipitation can significantly affect the precipitation analysis, forecast, and downscaling. Because of occasional overestimation or underestimation of small-scale summertime precipitation extremes, the numerical experiments presented …