运动学效应对登陆台风近地面风场模拟的影响

Impact of Kinematic Effects on Simulated Near-Surface Wind Field of Landfall Typhoons

摘要:

以2016年超强台风“莫兰蒂”为例，采用天气研究与预报模型（WRF）耦合加利福利亚气象模型（CALMET）的方法，提出了适用于台风条件下的CALMET运动学效应改进方案（KETT）。结果表明，KETT方案可以成功消除CALMET原有运动学效应带来的风场模拟系统性误差，并且10 m高度风速和风向模拟误差比原有方案分别降低10.8%和5.4%。在石蛇山区域，与不采用运动学效应相比，KETT方案10 m高度风速和风向的模拟误差均降低12%以上，能够更准确地反映局地地形对台风近地面精细化风场的影响。

Abstract:

A WRF (weather research and forecasting model) / CALMET (California meteorological model) coupled system was used to simulate the near-surface wind field of super typhoon Meranti in 2016. An improved scheme of kinematic effects of terrain for typhoons (KETT) was proposed. The results show that the systematic error of simulated wind fields near the typhoon center can be successfully eliminated by using the KETT scheme. Compared with the original kenematic effects, the root mean squared errors (RMSEs) of 10-m wind speed and wind direction can be reduced by 10.8% and 5.4%, respectively. Besides, both RMSEs of 10-m wind speed and wind direction with the KETT scheme can be reduced by over 12% than those without the kinematic scheme at Shishe Mountain, indicating that the impact of local terrain on the fine-scale typhoon wind structure near the surface can be better expressed by the KETT scheme.