CWRF边界层参数化对东亚近海热带气旋模拟的影响评估

Evaluation of impacts of CWRF boundary layer parameterization on the simulation of tropical cyclones over offshore areas of East Asia

基于CWRF模式结果,探讨了6种边界层参数化方案对30 a东亚近海热带气旋的强度、频数及路径模拟的可能影响。结果发现:CWRF模式中各边界层参数化方案模拟的热带气旋频数普遍较观测偏少,模拟强度相比观测也均偏弱。热带气旋的强度、频数及出现频次的空间分布对模式边界层方案的选取较为敏感。CAM3方案模拟强热带气旋的能力较其他方案偏好,ACM方案在多数年份模拟的热带气旋个数偏多,且在不同月份模拟的热带气旋生成频率与观测最接近,CAM3方案模拟的热带气旋出现频次与观测的偏差在大部分地区偏小。综合来看,CWRF模式中边界层参数化选用CAM3方案模拟热带气旋活动的性能较好。

Based on CWRF(Climate extension of Weather Research and Forecasting)model,the possible impacts of the 6 planetary boundary layer(PBL)parameterization schemes on the simulation of the intensity,frequency,and tracks of the tropical cyclones(TCs)that occurred over offshore areas of East Asia from 1986 to 2015 are investigated.It is found the TCs simulated by each PBL scheme in CWRF model have less frequency and weaker intensity compared with observations.The intensity,frequency,and spatial distribution of the simulated TCs are sensitive to the selection of PBL schemes.Strong TCs are well simulated by CAM3(Community Atmosphere Model Version 3)schemes.When simulated by ACM(Asymmetric Convective Model)scheme,the number of TCs is larger,and the frequency of TCs genesis in different months is the closest to that of observations.The difference of TCs’occurrence frequency between the simulation by CAM3 and the observations is relatively less in most areas.In all,the CAM3 scheme can better simulate TC activities than other PBL schemes in CWRF model.