EFFECT OF ATMOSPHERIC HAZE ON THE DETERIORATION OF VISIBILITY OVER THE PEAR RIVER DELTA
Wu Dui~ 1,2 Bi Xueyan~ 1 Deng Xuejiao~ 1 Li Fei~ 1 Tan Haopo~1 Liao Guolian~2 Huang Jian~11 Institute of Tropical and Marine Meteorology, CMA, Guangzhou 5100802 Department of Atmospheric Science, School of Environmental Science and Engineer, Sun Yai-sen University,Guangzhou 510275
The studies on the effect of atmospheric aerosol on climate and environment are hot issues in the current circle of international science and technology. In recent years, the pollution of aerosols is getting worse and worse over the Pearl River Delta (PRD). The cloud of aerosol could occur all year around, with an area of heavy pollution located in the western side of the estuary of the Pearl River. The haze weather mainly occurred from October to next April, resulting in visibility deterioration. Since the beginning of the 19 80s, haze weather has obviously increased and visibility dramatically deteriorated over the PRD. There were three times of big deterioration fluctuations accompanied with the development of economy, that is to say, the dust pollution period from the beginning to middle 1980s, the sulphate and dust pollution period in 1990-1997, and the dust, sulphate, and automobile exhaust pollution period from 2002. There was no indication that the long-term tendency of fog and light fog days is affected by human activities or economical development, and it was governed by the intrinsically inter-annual and inter-decadal variations of climate. The deterioration of visibility had close relation to the fine particles over the PRD. Half of monthly mean PM10 observations exceeded the day-mean critical value of national second graded standard(150 μg/m~3), and all of monthly mean PM_ 2.5 values exceeded the day-mean critical value of American national standard(150 μg/m~3), especially in October to next January, the monthly mean value of PM_ 2.5 almost reached twice the standard value, indicating that the fine particle concentration was very high. The ratio of PM_ 2.5 to PM_ 10 was also very high, and it could reach 58-77%, in particular in dry seasons. Therefore, the fine particle pollution dominates the present aerosol pollution over the PRD. In comparison with the data observed 15 years ago, the ratio of fine particles has obviously increased.
【Fund】： 国家自然科学基金(40375002 40418008);; “973”计划项目课题(2006CB403701);; 广东省自然科学基金(033029);; 广东省重点科技攻关项目(2004A30401002 2005B32601011);; 广州市应用基础研究项目(2004J1-0021)
【CateGory Index】： X513
【CateGory Index】： X513