The Relationship of PM Variation with Visibility and Mixing-Layer Height under Hazy/Foggy Conditions in the Multi-Cities of Northeast China
نویسندگان
چکیده
The variations of visibility, PM-mass concentration and mixing-layer height (MLH) in four major urban/industry regions (Shenyang, Anshan, Benxi and Fushun) of central Liaoning in Northeast China are evaluated from 2009 to 2012 to characterize their dynamic effect on air pollution. The annual mean visibilities are about 13.7 ± 7.8, 13.5 ± 6.5, 12.8 ± 6.1 and 11.5 ± 6.8 km in Shenyang, Anshan, Benxi and Fushun, respectively. The pollution load (PM × MLH) shows a weaker vertical diffusion in Anshan, with a higher PM concentration near the surface. High concentrations of fine-mode particles may be partially attributed to the biomass-burning emissions from September in Liaoning Province and surrounding regions in Northeast China as well as the coal burning during the heating period with lower MLH in winter. The visibility on non-hazy fog days is about 2.5-3.0 times higher than that on hazy and foggy days. The fine-particle concentrations of PM2.5 and PM1.0 on hazy and foggy days are ~1.8-1.9 times and ~1.5 times higher than those on non-hazy foggy days. The MLH declined more severely during fog pollution than in haze pollution. The results of this study can provide useful information to better recognize the effects of vertical pollutant diffusion on air quality in the multi-cities of central Liaoning Province in Northeast China.
منابع مشابه
The Relationship of PM Variation to Visibility and Mixing Layer Height under Haze/Fog Condition in Multi-Cities of Northeast China
The variations of visibility, PM mass concentration and mixing layer height (MLH) at four major urban-industry regions (Shenyang, Anshan, Benxi and Fushun) in multi-cities of central Liaoning over northeast China were evaluated from 2009-2012 to characterize the dynamics effect on air pollution. The annual mean visibilities were about 13.7±7.8km, 13.5±6.5km, 12.8±6.1km and 11.5±6.8km in Shenyan...
متن کاملA Total Bounded Variation Approach to Low Visibility Estimation on Expressways
Low visibility on expressways caused by heavy fog and haze is a main reason for traffic accidents. Real-time estimation of atmospheric visibility is an effective way to reduce traffic accident rates. With the development of computer technology, estimating atmospheric visibility via computer vision becomes a research focus. However, the estimation accuracy should be enhanced since fog and haze a...
متن کاملRevealing the impact of changing land use of the annual spatiotemporal boundary layer height (Kermanshah Case Study)
Introduction Atmospheric boundary layer (ABL), is the lowest part of the atmosphere. Its behavior is directly influenced by its contact with earth surface. On earth it usually responds to changes in surface radiative forcing in an hour or less. In this layer physical quantities such as flow velocity, temperature, moisture, etc., display rapid fluctuations (turbulence) and vertical mixing is st...
متن کاملAssessing variety mixture of continuous spring wheat (Triticum aestivum L.) on grain yield and flour quality in Northeast China
Wheat (Triticum aestivum L.) variety mixtures represent a relatively unexplored avenue for maintaining yield and improving flour quality. A field experiment was conducted to examine the responses of three spring wheat varieties in pure variety and in variety mixtures under continuous cropping in Northeast China. Three modern spring wheat varieties, along with a three-variety mixture and a t...
متن کاملAn Analytical Approach For Enhancement Techniques Over Multiple Foggy Images
Images plays a very important role in human being’s life. They are very useful in all the problems we came across day by day. Such as, satellite images are used for traffic analysis or in developed cities traffic analysis is also done through the CCTV cameras. But images which are captured under bad weather conditions suffer low contrast so as their quality also degrade with the changes in atmo...
متن کامل