Meteorological Conditions Contribute Toatmospheric Haze And The Recovery Method Research In Hohhot

With the rapid development and construction of HuBaoE urban agglomeration,the air pollution in Hohhot was continuously increasing and the composite characteristic was obvious.In January 2020 Hohhot was ranking the third lowest in 168key cities national wide.The haze weather with heavey pollution last for a long time and had a bad effect for the life and health for urban residents.It's typical for the air quality improvementto research the characteristics of haze weather in Hohhot and give out the reasonable advice.By using conventional meteorological data and air pollution monitoring data,we analyzetheAmbient air quality changing characteristic of Hohhot between 2013 to2017.and the time change regulation of fog and haze.We draw a conclution that the days with good air quality from 2013 to 2017 were on the rise,the seasonal variation was that the most heavist pollution appears in the winter,spring and autumn gets better,and summer is the best.Effected by the increasing number of vehicles,the main pollutants were on the decline except NO₂and O_3.By using NCEP reanalysis data,MICAPS data and high altitude detection data,we choose 7 typical fog weather process and 14 moderate haze process between2010-2014 to make the synoptic diagnostic analysis.By classifying the different type and building the corresponding conceptual models of meteorology,we can get a conclusion that the main circulation form of fog shows four different kinds,the atmospheric was steady and the inversion layer was not necessary,while the haze came out with a high humidity and the inversion layer was necessary.Analysis the atmospheric dynamic and thermodynamic structure of haze weather.Using Statisticalanalysis to find out the average wind speed and main wind frequency of the seven ground site in Hohhot from 1981-2017.we get a conclusion that the annual average wind speed 1.5-3M/s while the speed in WuChuan area was obviously on the high side,and a wind convergence zone appeared along the mountain of the downtown,Helingeer and Tuoketuo,which was adverse for the pollutant diffusion.By analyzing the correlation of boundary layer physical quantity and AQI,we find out that thickness of inversion layer and AQI shows a positive correlation of above 95%with a reliability of 0.01,which means that the thickness and strength of the inversion layer had a significant effect on the generation of haze,especially,thicker and stronger the layer,more severe the pollution.Based on the above analysis,we analyze the cause of the haze weather from several aspect like the meteorological diffusion condition,industrial pollution,automobile exhaust,straw burning,etc.in order to give out some reasonable control measures,which was meaningful to the prevention of haze weather.