PolarWRF microphysics’ schemes sensitivity to cloud droplets concentration in the Antarctic Peninsula region

• Main Authors: Chyhareva, A., Krakovska, S.
• Format: Conference Object
• Language: English
• Published: 2023
• Subjects: Antarctic; Antarctic Peninsula; Austral; Morrison; The Antarctic; Vernadsky Station; Antarc*; Ice Shelves
• Online Access: https://gfzpublic.gfz-potsdam.de/pubman/item/item_5021028

Clouds and precipitation impact the sustainability of polar regions in numerous ways, particularly melting ice shelves due to the scattered radiation or released heat by liquid precipitation are among the most significant impacts. In addition, clouds remain to be a source of uncertainties in weather and climate models due to the complexity of physical processes, lack of observations and necessity of microphysics parameterization. It is particularly noticeable in the Antarctic Peninsula region, where its transitional position for air masses and circulation enhanced by the mountainous ridge imposes significant difficulties in the simulation of clouds. This study focuses on the high-intensity precipitation events over the Antarctic Peninsula region during the austral autumn and winter. PolarWRF regional model forced by ERA5 reanalysis data and complemented with measurements from Vernadsky station. A sensitivity study was done with different numbers for droplet concentrations for Morrison’s and Thompson’s microphysical schemes. The phase of precipitation and its transition are well represented by the Thompson et al. scheme. The highest snowfall rate is found by the Morrison double moment scheme, which underestimates the presence of rain. Both schemes underestimate precipitation intensity compared to measurements from the automatic weather station at the Vernadsky station. The mixing ratio of ice particles and rain droplets was analyzed for the vertical cross-sections over the Antarctic Peninsula. Few cloud layers and their dynamics were distinguished. The results of modelling could be used in further cloud study however, verification remains to be a big difficulty in this region.