Assessing the Added Value of Dynamical Downscaling Using the Standardized Precipitation Index

摘要: In this study, the Standardized Precipitation Index (SPI) is used to ascertain added value of dynamical downscaling over contiguous United States. WRF as a regional climate model (RCM) dynamically downscale reanalysis fields compare values SPI drought timescales that have implications for agriculture and water resources planning. The generated by has largest improvement correlation with observations timescale increases. This suggests downscaled may be more reliable than larger-scale resource applications (e.g., storage within reservoirs). improves timing intensity moderate extreme wet dry periods, even in regions homogenous terrain. study also examines changes from 1988 three “drought busting” tropical storms. Each those events illustrates importance using resolve spatial extent droughts. analysis storms demonstrates while impact these on ending prolonged droughts improved RCM relative reanalysis, it remains underestimated. These results illustrate some limitations RCMs project drought.