典型盆地城市风廓线演变特征及模拟研究

Vertical Variation Characteristics and Simulation Study of Wind Profiles in Typical Basin Cities

摘要: 研究成都地区风廓线的演变特征具有重要的科学意义和实际应用价值。本文利用成都市温江气象站2020~2024年观测数据通过风速廓线、风向玫瑰图，总结归纳风廓线的演变规律，采用WRF数值模拟评估了常用的三种边界层参数化方案(YSU、MYJ、ACM2)对成都地区风场的模拟性能。结果表明：(1) 成都地区08时与20时风场垂直结构特征相似，多项式拟合可较好地表征风廓线变化特征；平均风速随高度呈现先增后减趋势，低层冬季平均风速最小夏季最大，中高层相反，春季、秋季特征相似；其中850 hPa主导风向为东北风，到700 hPa偏南风增加，500 hPa以西风为主导，季节主导风向在700 hPa及以上层次存在差异，而且夏季的风向转换较多。(2) 三种方案均能有效模拟出成都地区风场特征，通过模拟结果和观测对比显示，采用YSU边界层方案为最优参数化方案。

Abstract: Studying the evolution characteristics of wind profiles in the Chengdu area has significant scientific significance and practical application value. In this paper, based on the observation data of Wenjiang Meteorological Station in Chengdu from 2020 to 2024, through wind speed profiles and wind direction rose diagrams, the evolution laws of wind profiles are summarized and concluded. The simulation performance of three boundary layer parameterization schemes (YSU, MYJ, ACM2) for the wind field in Chengdu area is evaluated by WRF numerical simulation. The results show that: (1) The vertical structure characteristics of the wind field in Chengdu area at 08:00 and 20:00 are similar. The average wind speed shows a trend of increasing first and then decreasing with height. The average wind speed is the smallest in winter and the largest in summer in the lower layer, the opposite in the middle and upper layers, and similar in spring and autumn. Among them, the dominant wind direction is the northeast wind at 850 hPa, the southerly wind increases at 700 hPa, and the westerly wind is dominant at 500 hPa. There are differences in the seasonally dominant wind direction at 700 hPa and above levels, and the wind direction changes more frequently in summer. (2) All three schemes can effectively simulate the wind field characteristics in the Chengdu area. The simulation results and observational comparisons show that the YSU boundary layer scheme is the optimal parameterization scheme.