摘要
利用2004年3月27～29日北京沙尘暴期间观测的辐射、气象以及气溶胶质量浓度的资料,分析了该过程的地面辐射、气象要素以及气溶胶与辐射相互作用的变化特征。结果表明,沙尘暴期间紫外辐射的衰减与可见光辐射强度衰减规律不一致。紫外衰减主要受到细粒子浓度影响,同时紫外辐射占总辐射的比重与气溶胶中细粒子含量成负相关;而可见光辐射强度衰减与总辐射衰减同步。辐射变化和气溶胶质量浓度观测结果均表明,此次沙尘暴过程分为3个阶段,即,细粒子累积期、外地沙尘输入期和清除期。在沙尘暴期间地面一直维持一个低压、干冷的状态;当过程结束后,气压急剧增高,并在一段时间内处于高压控制之下。
An intensive experiment on dust storm was carried out in Beijing from 27 to 29 March 2004.Based on the measured dataset, the characteristics of solar radiation, the variation trend of atmospheric aerosol concentration (PM10 and PM2.5), the variation characteristic of meteorological factors, and, the relations between aerosol and solar radiation in the dust storm period were analyzed. The results showed that the ratio of ultraviolet radiation to global radiation was different from the ratio of photosynthetically active radiation to global radiation. The ratio of ultraviolet radiation to global radiation is influenced by the concentration of fine aerosol. There is a negative correlation between fine aerosol concentration and the ratio of ultraviolet radiation to global radiation in the dust storm period. But the photosynthetically active radiation has the same variable trend as the global radiation during the dust storm period. The dust storm can be divided into three stages, namely, accumulation of local fine particle pollutants, arrival of external particle, and clear-out of dust. In the second stage the ratio of PM2.5 to PM10 decreased significantly. The air was cold and dry with low pressure during the dust storm. When the dust was cleared out the pressure increased rapidly.
出处
《气候与环境研究》
CSCD
北大核心
2005年第2期265-274,共10页
Climatic and Environmental Research
基金
国家自然科学基金资助项目40222202
