东海近海海雾日变化特征及生成的水文气象条件分析

Analysis of the daily variation of sea fog in the East China Sea and the weather condition to the sea fog formation

统计分析了东海沿海5个海洋站点的水文气象历史数据,对该区域雾生的日变化特征及海雾维持的气象条件包括气-水温差、风向风速等做出了初步评价。结果显示,除南麂站外各站点上午有雾的情况最多,下午次之,夜间有雾的情况偏少。出雾时气-水温差的阈值大于平流雾形成所要求的气-水温差范围,说明东海沿岸也受非平流雾的影响。另外,多岛区域与开阔水域相比,近岸岛与远离大陆的岛屿相比,雾的日变化规律有着较为明显的差别。

Using the hydrographical and meteorological observation of five stations in the East China Sea, the re- lationship of sea fog forming with the air-sea temperature difference, wind speed and direction is analyzed. The weather conditions under which sea fog probably happens in the area are also discussed by using statistics meth- od. Main conclusions are as follows： for all stations except of Nanji, the frequency of fog occurs is higher in the morning than that in the afternoon and evening. Since the range of air-water temperature difference is wider than the conditions of advection fog forming, the East China Sea may be affected by other type of fog, such as radia- tion fog. Moreover, the daily variations of sea fog between the region surrounded by islands and the area in open water, the region close to mainland and the one far away to mainland, both have significant differences.