Analysis and characteristics of visibility in Shenyang from 2010-2012
【摘要】：Using the visibility data during 2010 to 2012 obtained at Shenyang Atmosphere Observation Center, the relationships between visibility, PM mass concentration and meteorological elements were statistically analyzed. The results show that: The monthly averaged visibility over Shenyang is higher in March and September with values about 19.0±4.3km and 17.1±4.3km, respectively. Low visibilities over Shenyang occur in January about 11.0±4.7km. Among the meteorological elements, wind speed was the main meteorological factor that influenced visibility and the PM mass concentrations. The number of days with visibility 19.0 km and visibility 10.0 km in Shenyang are 59, 123, 145 and 132, 119, 121 from 2010 to 2012. The relationship between visibility and PM indicated that human activities are already main sources of the pollutants, especially the fine particles which is the most important factor for the deterioration of visibility. The study shows an obvious diurnal variation and weekend effect of visibility and PM which are mainly due to human activities.