2017年邯郸市气象扩散条件评估分析

An Assessment Analysis of Meteorological Diffusion Conditions in Handan

2017年,邯郸市达标天数142 d,重污染天数43 d。年内出现3 d以上AQI>200的重污染过程6次,与2016年持平。全市年均静稳天气指数与2016年持平;年平均风速比2016年减小,小风日数增加,水平扩散能力较差;年均混合层高度与2016年同期基本持平,垂直扩散条件相当。2017年1—10月气象扩散条件总体不利,11—12月气象扩散条件好于2016年;2017年1—10月静稳指数为近5年最大,混合层高度最低,降水量最少,平均风速最小,小风日数最多,气象扩散条件相对较差;2017年10月气象扩散条件与2016年同期相比较差,2017年11月、12月气象扩散条件与2016年同期相比较好。

It was found that the air quality of Handan improved in 2017, as the number of heavy pollution days decreased to 43 days, and the number of days that reached standards increased to 142 days; meanwhile, in2017, the heavy pollution weather lasting more than three consecutive days with AQI>200 happened 6 times in Handan, similar to that in 2016. Also, the average annual stationary weather index in 2017 was almost the same as that in 2016; the annual mean wind speed in 2017 decreased when compared with that in 2016, while the annual small wind days increased, thus leading to poor horizontal diffusion ability; the average annual mixing layer height in 2017 was also almost the same as that in 2016, and so was the vertical diffusion condition. From January to October in 2017, the meteorological diffusion conditions were generally unfavorable, while in November and December, they were much favorable than that in 2016. From January to October in 2017, the stationary weather index was the maximum in nearly five years, with the lowest mixing layer height, minimum precipitation and mean wind speed, and the maximum number of small wind days, and thus resulting in relatively poor meteorological diffusion conditions. So, from January to October in 2017, the average meteorological diffusion conditions decreased significantly compared with that in 2016 in the same period, while from November to December in 2017, the conditions were much favorable than that in 2016.