WRF微物理和边界层组合方案对气旋过境海气通量模拟的敏感性研究

利用中尺度模式WRF (Weather Research and Forecasting Model)3.2版本模拟了一次冬季温带气旋过境过程，分析海气通量模拟对9种微物理方案和3种行星边界层方案的敏感性。LIN方案和YSU方案组合实验模拟出的平均风速最大，WSM3方案和ACM2方案组合平均风速最小。总体上，边界层方案对感热和潜热模拟的影响大于微物理方案的影响，风暴过境前，各实验模拟的海气通量对参数化选择不敏感；风暴期间，不同边界层参数化方案风速模拟差异较大，气温也存在差异，从而导致感热模拟差异较大；风暴过后，不同参数方案感热和潜热模拟差异较大，主要由于风速、气温和比湿综合作用导致。各种组合模拟出的海气通量均存在系统误差，这主要受近地面边界层方法限制，因此WRF 3.2还需进一步改善。

Sensitivity of air sea flux to microphysical schemes and planetary boundary layer parameterizations in WRF during a cyclone passage

The WRF (Weather Research and Forecasting Model) Version 3.2 was used to analyze the sensitivity of simulated air sea flux during a cyclone passage. Combinations of 9 microphysical parameterizations and 3 planetary boundary layer parameterizations were tested. LIN YSU case has the strongest mean wind while WSM3 ACM2 case has the weakest. Generally, the influences of planetary boundary layer on the simulation of sensible and latent heat flux are greater than those of microphysical schemes. Before the storm, all cases show that the air sea fluxes are not sensitive to the parameterization; during the storm, planetary boundary layer schemes influence the simulation of wind speed and air temperature, thus causing significant difference in simulated sensible heat fluxes; after the storm passage, test cases produce significant difference in both sensible and latent heat fluxes, which are mainly contributed by the combination effect of simulated wind speed, air temperature and specific humidity. Compared with observations, all simulated air sea fluxes have large systematic errors, which are probably due to the surface layer parameterization, indicating that the surface boundary layer parameterization in WRF 3.2 still needs to be improved.