江苏省大雾的变化特征及气溶胶对其影响

Heavy fog's climate characteristics and possible effcet of aerosol in Jiangsu Province

通过分析近50年江苏长序列大雾日数、持续时间、时空分布规律以及其成因,探讨气溶胶对大雾形成的可能机制.研究结果表明:大雾可能出现在任何时候,但在清晨和秋季出现的频率最多.它们的变化可从该区的季节环流背景特征和雾的形成机理得以解释.年代际大雾日变化大体呈现出抛物线(先升后降)分布特征,而大雾持续时间一直呈波动增长趋势,气象因素不能全部解释其变化特征.气溶胶对大雾形成和持续时间可能有重要影响,气象因素和气溶胶共同作用可解释江苏省年际大雾日变化和大雾持续的变化特征.

Heavy fog days, duration hours, temporal and spatial distribution and the causes of Jiangsu heavy fog in recent 50 years were analyzed to explore aerosol effect mechanism on heavy fog formation. The result show that heavy fog might occur at any time, but the most frequent time was early morning and autumn. The changing rule could be explained by seasonal circulation background characteristics of the area and the fog formation mechanism. The days of heave fog changes annually showed parabolic distribution （up then down） in recent 50 years, and the duration hours of heavy fog shows a volatility rising tendency. Meteorological factors could not explain all the variation characteristics. Aerosol might have important effects on the formation and duration of heavy fog. The combined effects of meteorology factors and aerosol could explain the changing characteristics of heavy fog days and duration hours.