摘要
不同类型的背景场和海陆风对珠江三角洲地区大气灰霾有不同的影响。作者主要利用空气质量模式系统Models-3(MM5/SMOKE/CMAQ)研究离岸型背景风和海陆风对珠江三角洲一次灰霾天气的影响,结果表明,中尺度气象模式MM5对珠江三角洲地区这次灰霾天气的气象模拟,较好地模拟了风速和风向的变化。多尺度空气质量模式CMAQ模拟出了PM10浓度的变化,与观测值比较一致。在这次灰霾天气过程中,由于离岸型背景风与陆风风向一致,在陆风维持的情况下,内陆源区的PM10被输送到沿海地区,导致沿海城市和海面上PM10浓度比较高;而在海风维持的情况下,海风与离岸型背景风方向相反,造成海风较小,致使整个珠江三角洲地区灰霾天气都比较严重。敏感性试验结果表明离岸背景风和海陆风的相互作用对灰霾天气的生成与分布有重大的影响。
The effects on atmosphere haze over the Pearl River Delta （PRD） are different with the different background flow and sea-land breezes （SLBs） . In this paper, the Models-3 modeling system is used to study the role of the off-shore background flown and the SLBs played on haze weather over the PRD region during the period of 26 - 30 September 2004. The modeling system includes air pollutant emission model SMOKE, meteorological data from MM5, and Community Multi-scale Air Quality （CMAQ） （Version 4.5）, a 3D chemistry transport air quality model. A three-level-nested grid domain with spatial resolutions of 36, 12 and 4 km is designed for the study region.The comparison between the observation and model results shows that the model is able to reproduce the main characteristics of the surface winds and directions The modeling system can simulate the variations of particulate matter with aerodynamic diameter less than 10/~m （PM10）. The land breeze （LB） direction is coincident with the off-shore background flow. As a result, PM10 can be transported to the coast and ocean area by the LB, leading to high PM10 concentration. The sea breeze （SB） that wind direction is opposite to the off-shore background flow is small, causing the entire PRD region heavy haze weather. The sensitivity experiment results show that the interaction between off-shore background flow and the SLB has important effects on the generation and distribution of haze weather.
出处
《大气科学》
CSCD
北大核心
2008年第3期530-542,共13页
Chinese Journal of Atmospheric Sciences
基金
国家“863”项目2006AA12Z207
国家重点基础研究发展规划项目2002CB410801
关键词
背景风
海陆风
灰霾天气
PM10
background flow, sea and land breezes, haze weather, PM10
