Beijing Summer, Autumn O3 Characteristics Of Near-surface Observational Studies,

Beijing is the political , economical, culture center of China. Especially Beijing is the front for city of Summer Olimpic Games in 2008 .So its air quality is compelling . Though focus renovate air quality in Beijing have improved already. But however a lot of problems of air quality pollution need solve. Besides the pollution of fine-particle, Photo-chemistry smog also are very important environment question. This focucing on summer ozone pollution and high ozone concentration in Ming Tomb We have observated and investigated. A comprehensive observational experiment on ozone and its precursors at urban (on the top of main building at Beijing Dancing college) and suburb an (ZhaoLing of Ming tomb) sites of Beijing was carried out during the period from September 7tol7, 2001. The experiment of O₃ and precursors carried out at 3 sites, respectively in 2002 and 2003. The act of aiming is the characteristics of O₃ precossors during O₃ pollut ion. The all instrument of SO₂, O₃, NO_x and CO have made in TE companies of U. S. A All data have achieved in strict quality control. The follow are results:1. High ozone pollution is important at air pollution questionin summer in Beijing. The super scale is 35%, 25%, 10% at dancing colledge chaoyang and shunyi in summer in 2002,respectively. The superscale at trainingCenter Center of Olimpic, Observatory is 33.3%, 66.7%, 48%, respectively.2. If flourly ratio of NO₂/NO exceed the certainty value and presents before 16: 00, then the hourly ozone concentration in the afternoon wi 11 be superscale. The critical value will change depende on the site and year.3. on certain instance when the VOC concentration is high, then the correspondence ozone concentration also is high. But the 03 concentration is restricted by the ratio of NO₂/NO sometimes.4. The daily mean ozone concentration at surburban is higher it than at urban. The ozone concentration at suburb in daytime is larger than it at urban. The ozone concentration at urban in nighttime is less than in at suburb. Main reason is NO at urban in nighttime maintain relatively high value, process it depletes more 03 through "titration process" at urban site.5. whether the hourly NO concentration larger than 10ppb ( ) corresponding hourly ozone concentration approachs zero.6. The low ratio of NO2/NO is corresponding with low surface ozone. Ratio of NO2/NO at urban in nighttime is little than it at suburb.7. By one dimension photochemistry model, We simulate basically diurnal change of O₃, NO, NO₂, CO and SO₂ on September. 9 of 2001 in stability weather and explain the control factors for diurnal change of O₃, NO, NO₂, CO and SO₂. The preliminary analysis shows the O₃ concentration is sensitive to NMHC. The increase or decrease of NMHC concentration results ozone concentration is change distinctly. NO and NO₂ is controled by the photochemistry , but CO and SO₂ is controled by the transportation. The cause for increasing of NO, CO and SO₂ concentration during 20: 00 23: 00 on September. 9 of 2001 is due to weak vertical diffuse and pollutants accumulated at low atmosphere in the night. In fact, the produce and deplete mechanism of O₃ is complex and the transportation is important factor for O₃ and precursors. One-dimension can open out the main factors effecting on O₃ concentration. But we still need use 3-dimensions model explain more phenomena.The conclution in the paper only is given by few experienments. The O₃ pollution in summer of Beijing is more complex question of air pollution, we need continuly study and validate in the future.