| We use the mass concentration of PM2.5and M10,which were observed on 8,80, 240m platform in 325m Beijing meteorological tower from 2005 to 2006,the cubage concentration of O3,NO,NO2,NOx,which were observed on 8,80,240 m platform in 325m Beijing meteorological tower from August,2004 to August 2007;and the PM2.5,M10,O3,NO,NO2,NOx observations of Beijing,Tianjin,Tangshan in August 2007,which camme from the Beijing Area atmosphere pollution observe net,add the API of Beijing,Tianjin,Tangshan,Datong,Taiyuan,Chifeng,Jinan,Shijiaxzhuang from 2004 to 2006,the air temperature,air pressure,dew point,visibility,wind,to research the local pollution of Beijing and the area pollution of Beijing surrounding area.The results are as follows:(1)The primary contamination of Beijing Area is PM10,it is more serious than the pollution,caused by sulfur dioxide.In 2006 the Beijing aergsol pollution is serious, the annual average concentraation of PM2.5 and M10is 162.1±92.3,77.4±53.7μg·m-3 respectively.The annual average ratios of PM2.5to PM10is 50.5%,the PM2.5mass is an half of PM10mass.Primrose season the PM10concentration,goes up 215.6±125.9μg·m-3caused by dust storm.PM2.5pollution is serious.in summer,from. 8,120 to 240m the mensal average PM2.5concentration were.66.8±40.3,64.4±40.7 and 58.8±39.3μg·m-3respectively,they all overstep WHO range more than one multiple,show a very thick haze layer structure oyercast the top of Beijing city.(2)The concentrations of PM2.5show a very distinct variation.There is an obvious vertical layer,structure in August.The concentrations of PM2.5in 240 meter lower than the concentrations in 8,80 meter,and it show a very clear cycle with two peaks.The diurnal variations of the PM2.5concentration in the low layers(8 and 80, meter)show a very.clear cycle with one peak.The pollutions is transported from ground to the high layer by the air onflow and air convection at afternoon,so the concentrations of PM2.5in 240-meter layer is higher than.the concentrations in the. other layers at 15:00.(3)During the gas contamination of Beijing,NOx pollution is light,the annual average concentration of NOx in 2005 and 2006 is 66.5±71.4,48.6±42.1 ppb respectively,the NOx concentration decrease year after year.But ozone pollution increase obviously,the annual average concentration of ozone in 2005 and 2006 is 9.3±23.7,18.3±22.3 ppb respectively,and the average concentration of ozone from January to August in 2007 is 24.0±26.8ppb.Ozone pollution in August is very distinct. In August of 2005,2006,2007,the ozone mensal average concentration is 22.4±21.9, 29.7±31.6 and 27.7±29.6 ppb respectively.There was an obvious vertical layer structure of Ozone,especially at night.From 8-280m the ozone concentration at night arel0,20,and 30ppb.The Ozone deposit at night,and make the ozone concentration increase in the next day.(4)In the "car drive selectivity" days,(from 17th to 20th of August in 2007),the daily average NO concentration is 5.1±9.3ppb,the daily average NO2 concentration is 26.7±13.5 ppb,they are lower than the average concentration of the other days in August,reduce rate of NO and NO2 are 43.9%,25.1%respectively.The daily average ozone concentration is 41.0±31.4 ppb,overtop 10.8 ppb to the average concentration of the other days in August,increase rate is 36%.As a result of the weather concentration of PM2.5,is increased 11.5μg·m-3day-by-day.The "car drive selectivity" reduces the car in the road,and slower the PM2.5increased extent.(5)PM2.5are installed on 8,80,240 m platform in 325 m Beijing meteorological tower during summer and autumn in 2007.Results show that there is an obvious vertical distribution of PM2.5concentration in diffreent weather condition.There is an obvious vertical distribution of PM2.5concentration in diffreent weather condition.During the fog period(11.5-6),from 8-240m the daily average PM2.5 concentration are 352.6±79.3,224.7±69.0 and 214.8±32.8μg·m-3respectively.On 6th of Nov.,the PM2.5concentration altere obvious.In haze weather condition(8.19-20), PM2.5concentration mix uniformly,the daily average concentration in 8,80,240 m are 89.8±29.3,88.9±29.8 and 90.0±31.7μg·m-3on 19th of August.During the sunshine condition(8.22-23),The concentrations of PM2.5show a very distinct diural variation.There is an obvious vertical layer structure,especially at night.On 23rd of Aug.,8-80 m the aerosol mix uniformly the daily average PM2.5concentration is 32.6±13.1μg·m-3,and the concentration of 240 m is 27.4±13.5μg·m-3.The particle of fog are mainly from local sources.However,the particle of haze are maily from regional sources,and show increased setrend of concentration accumulated.There is a elimination process of PM2.5during the continuously fine days.
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