Sensitivity of the Planetary Boundary Layer and Cloud Microphysics schemes to the drivers of dispersion and transportation of aerosols

Abstract The Planetary Boundary Layer (PBL) is the lowest layer of the atmosphere that interacts with the Earth’s surface, and all major meteorology happens within this layer. This paper investigates the simulation of PBL Height (PBLH) and its sensitivity to meteorological parameters as a driver of aerosol dispersion and transport. Four simulations at 6 Km resolution using the Weather Research and Forecasting (WRF) model are run with two PBL schemes (ACM2 and YSU) combined with two Microphysics schemes (LIN and Morrison) for the year 2015 over the European domain. The simulated PBLH and other meteorological parameters that drive the PBL genesis, like temperature and wind speed, are analysed seasonally. In addition to the domain, a few locations from European Aerosol Lidar Network (EARLINET) representing various topography across the domain are chosen for analysis. The model performance in simulating the PBLH, temperature, and wind are examined using various statistical metrics involved in the Taylor diagram and Standard Deviation Error (STDE) methods. The study illustrates the comparisons of model performances for each variable over the domain and at selected station locations near the surface as well as the interfacial layer. We analyze how high (often overestimated) wind speeds affect the development of the Planetary Boundary Layer (PBL), particularly in complex terrains, on a seasonal scale. Our findings attribute unbalanced wind dynamics as a significant factor in this process. The STDE of microphysics schemes combination with YSU scheme shows a relatively 8-20% lesser error than other combinations across the seasons. Despite encountering notable errors over complex terrains, the YSU PBL scheme has performed better due to its ability to handle a wide range of atmospheric conditions.