2019年冬季邢台近地层风场特征分析与污染系数研究

Analysis on Characteristics of Near Stratum Wind Field and Study on Pollution Coefficient in Xingtai in Winter 2019

摘要: 利用中国气象局邢台大气环境野外科学试验基地100 m通量观测塔2019年12月到2020年2月共10层风向、风速观测数据，对邢台冬季近地层风速、风频、污染系数等进行分析。结果表明：1~100 m高度平均风速呈现明显日变化特征，日间平均风速明显大于夜间平均风速，其中1~100 m平均风速在日间为3.70 m∙s−1，夜间为2.95 m∙s−1；随高度增加，日间和夜间的平均风速均呈增加趋势，但日间与夜间的平均风速差呈逐渐减少的分布；风切变指数与风速呈负相关关系；各高度盛行风向均以北风及相近风向为主；各高度污染系数最大值为北风及相近风向，污染系数整体呈现出低层大、高层小的趋势；PM2.5和PM10浓度平均值与污染系数相关性高层好于低层，其中在80 m高度呈明显负相关；污染系数的最大值出现在北风风向，随高度增加，PM2.5和PM10平均质量浓度呈波动下降的趋势。

Abstract: Based on the observation data of wind direction and wind speed in 10 layers from December 2019 to February 2020 of the 100 m flux observation tower in Xingtai atmospheric environment field scientific experiment base of China Meteorological Administration, the wind speed, wind frequency and pollution coefficient in winter near Xingtai were analyzed. The results show that: the average wind speed at 1~100 m height presents obvious diurnal variation, and the average wind speed at daytime is significantly higher than that at night, among which the average wind speed at 1~100 m height is 3.70 m∙s−1 at daytime 2.95 m∙s−1 at night; With the increase of altitude, the average wind speed in daytime and at night increased, but the difference between the average wind speed in daytime and at night decreased gradually; There is a negative correlation between wind shear in-dex and wind speed; The prevailing wind direction of each altitude is mainly north wind and near wind direction; The maximum value of each height pollution coefficient is north wind and similar wind direction, and the pollution coefficient shows a trend of large in low level and small in high level; The correlation between PM2.5 and PM10 concentrations and pollution coefficient is better in the upper layer than in the lower layer, and there is a significant negative correlation at the height of 80 m; The maximum pollution coefficient appeared in the north wind direction, and the average concentration of PM2.5 and PM10 showed a downward trend.