Performance Evaluation of Different PBL and Microphysics Parameterizations in WRF for Simulating Pre-Monsoon Thunderstorms Over Delhi-NCR

Abstract

The present study evaluates the performance of three different planetary boundary layer (PBL) schemes, i.e., Mollar-Yamada-Jenjic (MYJ), Yonsei University (YSU), and the Asymmetric Convective Model version 2 (ACM2) and four microphysics (MP) schemes, i.e., Lin, WRF Single Moment (WSM6), WRF double moment (WDM6) and Thomson over Delhi National Capital Region (NCR). For this purpose, a composite analysis of 10 different thunderstorm cases occured during 2008 to 2020, has been considered. ECMWF 5th generation reanalysis (ERA5) highresolution initial and boundary conditions have been provided to the WRF model for this purpose. Global Precipitation Measurement (GPM) and IMDAA reanalysis datasets have been used for validation purposes. The study highlights that for the simulation of precipitation and 10 m wind speed, YSU scheme performs better than the other two. For temperature and relative humidity prediction, the performance of ACM2 and MYJ, respectively, is found to be better. Accordingly, YSU PBL is considered for carrying out the MP sensitivity, and the results indicate that the Lin scheme could capture the temporal variability and intensity of precipitation better than the other three schemes. WSM6 also performs considerably well. However, all the simulations exhibited poor spatial distribution of rainfall pattern. Thus, the study infers that a combination of YSU PBL and Lin MP schemes could be used in the further studies for thunderstorm simulations over Delhi NCR and its neighborhood.