变性再发展热带气旋Yaji(2006)的数值模拟研究

NUMERICAL SIMULATION ON THE EXTRATROPICAL TRANSTION OF TROPICAL CYCLONES YAJI(2006)

利用中尺度模式WRF对2006年14号热带气旋Yaji的变性过程进行了双重嵌套模拟。结果表明,采用高分辨率的TRMM/TMI卫星反演SST资料,在第一重区域(网格距为15km)采用WSM3微物理方案和Betts-Miller对流参数化方案,在第二重移动嵌套区域(网格距为5km)采用Lin微物理方案,不采用对流参数化方案,模式能较好地模拟Yaji的路径和变性前后的强度演变,其中模拟的路径平均误差为64km,强度平均误差为2.5hPa,模拟的风场分布与Quickscat卫星反演的风场分布也较为吻合。利用模拟资料还研究了Yaji变性过程中的非对称流特征。

A two-nested grid of Weather Research and Forecasting Model （WRF） was used to simulate the extratropical transition process of tropical cyclone Yaji （No. 14 of 2006） which forced by the high-resolution sea surface temperature （SST） retrieved from TRMMfrMI. The results show that the model with the WRF Single-Moment 3-class Microphysics Scheme （WSM3） and Betts- Miller-Janjic cumulus parameterization scheme for the outer grid of 15 km, and the Lin microphysics scheme and without cumulus parameterization scheme for the finest grid of 5 km performed well for the track and intensity variation before and after the extratropical transition process of Yaji. The mean error for track simulation is about 64 km, whereas the mean intensity error for the minimum sea level pressure at the center of Yaji is 2.5 hPa. Furthermore, the simulated wind field is consistent with that retrieved from Quickscat. The asymmetric features of the flow during the extratropical transition process are also investigated.