The Characteristics of Precipitation and Latent Heating Profiles in MCS interacting with Heavy Dust Storm - Case Study using both Satellite Observation and WRF modeling

Abstract:

It has been proposed that the impacts of aerosols on microphysical processes of cloud formations can be transferred to the cloud thermodynamic processes via the link of changing latent heat (LH). And such interactions are controlled by different mechanisms varying with vertical altitude and temperature. Observations from satellite (such as the Global Precipitation Measurement GPM satellite measuring three dimensional structures of precipitation) and simulations from Cloud Resolving Model (CRM, such as the Weather Research and Forecasting WRF model) in real atmosphere provide us powerful tools to study this processes. However, the validation of WRF simulated vertical profiles of precipitation and LH comparing to GPM observations, particularly under heavyly dust-laden circumstance, were not investigated thoroughly. In this study, the characteristics of precipitation and LH profiles in a case of deep convective front system mixing with dust storm on May 3^rd 2017 in China was analyzed using multiple satellite observations and retrievals (including GPM DPR precipitation profiles, three LH retrievals) and associated WRF simulations. The performance of WRF simulations of precipitation vertical structure wer evaluated at first. The similarity and discrepancy of LH retrievals among the three satellite products were discussed. The potential impacts of dust aerosol on the vertical structure of precipitation and LH were investigated. The WRF simulated surface precipitation rate showing fairly well correlation with GPM measurements and the correlation coefficient (R) increased with the size of validation grid. And the WRF simulated vertical structure of precipitation show positive correlations with GPM as seen from Contoured Frequency by Altitude Diagram (CFAD). Dust only invaded into very narrow (perpendicular to the front line) and long (along the front line) area inside the storm. In the well mixing area, we found significant enhancement of ice formation and LH release due to dust IN effect. However in the prefrontal and postfrontal area, dust made insignificant impacts on the vertical structure of precipitation and LH. Different microphysical parameterizations of IN and cloud microphysics in WRF may insert remarkable effects on the detailed simulations of precipitation and LH.