Study On The Characteristics And Sources Of Haze Pollution Over The Southern Hebei Area

As a new disastrous weather events, haze has attracted more attention in recent years. The Beijing-Tianjin-Hebei area is one of the regions having the most severe haze pollution in China. Within this area, the haze pollution of southern Hebei area is more serious than the Beijing-Tianjin area.This paper is aiming to analyze the charateristics and sources of the severe haze pollution over the southern Hebei area by senario analysis using the MM5-Models-3/CMAQ modeling system, to provide scientific information and support to the policy making in comprehensive air pollution controls over this area.First, the haze days were identified for the ten years from2001to2010. It was found that the haze appearance showed clear seasonal variations. The haze pollution was the most serious in wintertime, then in summer and autumn. The lowest frequencies appeared in May, April and June. December2007, which has the most serious haze pollution during the10years from2001-2010, was chosen as the modeling period. The MM5-Models-3/CMAQ modeling system was applied in the regional scale modeling over Hebei and surrounding regions. The air quality daily report of86cities of the mainland China and the air quality daily report data of the major cities in Hebei Province was used in the evaluation of the modeling results, which shows that the simulations agree well with the observations. The model perfomance is acceptable.Besides the base case, the senarios of zero anthropogenic emissions in Hebei area, southern Hebei area and northern Hebei area was simulated as well. In the modeling period, the haze pollution was more severe along the Shijiazhuang-Xingtai-Handan, as to the visibility deterioration. The local source is the major source of the haze pollution in southern Hebei. The contributions of southern Hebei to PM2.5concentrations are60.5%(Handan) to63.2%(Shijiazhuang), and the contributions to Bext is58.2%(Xingtai) to59.4%(Shijiazhuang, Handan); the contributions of northern Hebei to PM2.5concentrations are4.6%(Handan) to7.3%(Shijiazhuang). and to Bext is4.3%(Handan) to7%(Shijiazhuang); the contributions of surrounding areas to PM2.5concentrations are25%(Shijiazhuang) to29.3%(Handan), and to Bext is30.2%(Shijiazhuang) to34.6%(Handan).