成都地区2012年PM10污染过程气象条件分析

Analysis on Meteorological Conditions during PM10 Pollution of Chengdu in 2012

利用PM10日平均值统计资料、NCEP 2.5°×2.5°分析资料以及温江站探空资料,针对2012年发生在成都的13次PM10典型污染过程进行了环流背景、动力条件、稳定度条件以及水汽条件的分析。结果表明:(1)PM10典型污染过程多发生在南支波动较弱的环流型下,我省受偏西气流或西北气流控制。(2)大气中低层垂直运动较弱,低层为弱辐合,辐合层次较低,不利于污染物的水平和垂直扩散。(3)对流层中下层中常有逆温层或等温层存在,大气热力状态较稳定。(4)大气多为上干下湿的状态,湿层较浅薄。

Based on the daily PMI0 data, sounding data of Chengdu and the 2.5 ~ x 2.5 ~analysis data of NCEP, the analysis on meteorological conditions, including circulation background, dynamic conditions, stability conditions and moisture conditions, were carried out against thirteen typical PM10 pollution processes. The results indicate that： 1 ） Sichuan Province is u- sually controlled by the westerly flow or northwest flow during PM10 pollution process, with the South Wave being weak. 2 ） The vertical motion in the middle and lower atmosphere is weak, with slight convergence in the relatively low level, which is unfavorable to the horizontal and vertical diffusion of pollutants. 3） The atmosphere is rather stable with a temperature inversion or isothermal layer in the lower troposphere. 4） The humidity layer is shallow when the upper air is relatively dry.