石家庄市一次重污染过程气象条件分析

对石家庄市2016年12月14—23日一次重污染过程的逐时空气质量和气象资料进行了分析。结果表明,低压均压类天气控制下,较高的相对湿度和水汽压,<2.5 m/s的低风速以及<500 m的混合层高度是该次重污染形成和持续的重要原因。当风速<2.5 m/s,且相对湿度>45%或水汽压>3.6 hPa时,空气质量明显较差;当风速<2 m/s,且湿度>65%或水汽压>4 hPa时,污染级别达到严重污染;该次重污染形成与维持的地面气压临界值为1017 hPa,当气压>1017 hPa时,环境空气质量相对较好;当气压<1017 hPa时,更容易发生严重污染。

Analysis of Meteorological Conditions of a Heavy Pollution Process in Shijiazhuang

The hourly air quality and meteorological data during a heavy pollution process from 14 to 23 December 2016 in Shijiazhuang city were analyzed. The results showed that when the ground weather was controlled by the low pressure and equal pressure type, high relative humidity and vapor pressure, low wind and low mixed layer height were the important reasons for the formation and sustainability of the heavy pollution. When the wind speed was less than 2.5 m/s and the relative humidity was more than 45% or the vapour pressure was more than 3.6 hPa, the air quality became worse. When the wind speed was less than 2 m/s and the humidity was more than 65% or the vapour pressure was more than 4 hPa, the condition of pollution became serious. The critical value of ground pressure for the formation and maintenance of the heavy pollution was 1 017 hPa. When the air pressure was higher than 1 017 hPa, the air quality was relatively good. When the air pressure was lower than 1 017 hPa, serious pollution was more likely to occur.