云微物理参数化方案对地面气温模拟性能的评估与改进OACSTPCD

The late afternoon near-surface air temperature plays a pivotal role in the initiation and evolution of convective processes,rendering its accurate prediction a fundamental requisite for mesoscale numerical modeling endeavors.This study assessed the simulation outcomes of five representative cloud microphysics parameterization schemes concerning the near-surface air temperature over East China during a cold cloud event employing WRFv3.9.1.Evaluation outcomes reveal substantial deviations in simulated near-surface air temperature during late afternoon and mid-night across all schemes,with the WDM6 scheme demonstrating superior performance in replicating near-surface air temperature,while the Thompson scheme exhibits the least satisfactory results attributed to its deficient cloud ice content.Consequently,further evaluation and improvement of the WDM6 scheme were conducted.Sensitivity experiments were devised,involving adjustments to parameters such as ice nucleus concentration,initial cloud condensation nuclei count,scheme optimization,and replacement of autoconversion process formulas governing cloud water to rainwater transition within the scheme,aimed at enhancing the fidelity of near-surface air temperature simulation by the WDM6 scheme.Sensitivity test outcomes indicate that substituting the Grabowski formula for the Berry formula,delineating the autoconversion process within the WDM6 scheme,enhances cloud water content and effectively improves near-surface air temperature simulation.Furthermore,validation of the improved WDM6 scheme was conducted against a meiyu event.Ultimately,integration of the improved WDM6 scheme into the Precision Weather Analysis and Forecasting System(PWAFS)model in Jiangsu Province significantly enhances the model's capability in simulating late afternoon near-surface air temperature,thereby furnishing crucial technical support for its operational implementation.