长江干流航道超高分辨率近地表风场数值模拟——以武穴航段为例

Ultra High Resolution Numerical Simulation of Near Surface Wind Field in the Main Waterway of the Yangtze River—A Case Study of the Wuxue Section

为保证长江水上交通安全,需要深入研究长江航道复杂地形的风场特征。本研究利用中尺度WRF模式结合微尺度CALMET诊断模型对长江干流航道上武穴航段进行30 m超高水平分辨率近地表风场模拟。结果表明:1) 不论是月平均小时风速,还是月最大小时风速,均存在两个大风速分布区,河流上游北岸山地区和河流中下游南岸区。2) 模拟区的风场存在显著的季节变化趋势。7月风速是最弱的月份,4月风速是最大的月份。3) 地形对风速存在一定的影响。富池镇南部的大岭山和长江北岸的土山的风速强度为模拟区平均风速和小时最大风速的高值区,富池镇附近的水域相对高于其他水域风速。复杂的地形会对水体上风场产生局地的影响,因此需要加强类似地形水域的风场监测,确保通航环境安全。

For the water transportation’s safety in the Yangtze River, the waterway surface wind field characteristics along the complex terrain of the Yangtze River need to be further studied. This study uses the mesoscale meteorological model-WRF and the diagnostic model-CALMET to simulate the near-surface wind field within ultra-high horizontal resolution of 30 m near the Wuxue section of the Yangtze River main waterway. It is shown that: 1) There are two large wind speed zones, both in terms of monthly average hourly wind speed and monthly maximum hourly wind speed, in the up-stream northern bank mountain area and the downstream southern bank area. 2) The wind field in the simulation area has a significant seasonal period. July has the weakest wind speed, and April has the strongest wind speed. 3) Terrain has a certain impact on wind speed. The high wind speed areas are in the southern area of Fuchi Town, which is the Dalingshan and the Tushan on the north bank of the Yangtze River. The wind speed in the water area near Fuchi Town is relatively higher than other water areas. Complex terrain will have a local impact on the wind field over the water, so it is necessary to strengthen the wind field monitoring in waterway similar to near terrain and ensure safe navigation environment.