Microphysical properties of sea fog and correlations of these properties were analyzed based on the measurements from a comprehensive field campaign carried out from 15 March to 18 April 2010 on Donghai Island （21...Microphysical properties of sea fog and correlations of these properties were analyzed based on the measurements from a comprehensive field campaign carried out from 15 March to 18 April 2010 on Donghai Island （21°35″N, 110°32″5′E） in Zhanjiang, Guangdong Province, China. There were four types of circula- tion pattern in favor of sea fog events in this area identified, and the synoptic weather pattern was found to influence the microphysical properties of the sea fogs. Those influenced by a warm sector in front of a cold front or the anterior part of low pressure were found to usually have a much longer duration, lower visibility, greater liquid water content, and bigger fog droplet sizes. A fog droplet number concentration of N≥1 cm-a and liquid water content of L≥0.001 g m-a can be used to define sea fogs in this area. The type of fog droplet size distribution of the sea fog events was mostly monotonically-decreasing, with the spectrum width always being 〉20 μm. The significant temporal variation of N was due in large part to the number concentration variation of fog droplets with radius 〈3 μm. A strong collection process appeared when droplet spectrum width was 〉10 μm, which subsequently led to the sudden increase of droplet spectrmn width. The doln- inant physical process during the sea fog events was activation with subsequent condensational growth or reversible evaporation processes, but turbulent mixing also played an important role. The collection process occurred, but was not vital.展开更多
基金mainly provided by the Meteorology Fund of the Ministry of Science and Technology (Grant No. GYHY[QX] 2007-6-26)the National Natural Science Foundation of China (Grant No. 41275151)+1 种基金the Qing-Lan Project for Cloud-Fog-Precipitation-Aerosol Study in Jiangsu Province, the Graduate Student Innovation Plan for the Universities of Jiangsu Province (Grant No. CX10B 292Z)a project funded by the Priority Academic Development of Jiangsu Higher Education Institutions
文摘Microphysical properties of sea fog and correlations of these properties were analyzed based on the measurements from a comprehensive field campaign carried out from 15 March to 18 April 2010 on Donghai Island （21°35″N, 110°32″5′E） in Zhanjiang, Guangdong Province, China. There were four types of circula- tion pattern in favor of sea fog events in this area identified, and the synoptic weather pattern was found to influence the microphysical properties of the sea fogs. Those influenced by a warm sector in front of a cold front or the anterior part of low pressure were found to usually have a much longer duration, lower visibility, greater liquid water content, and bigger fog droplet sizes. A fog droplet number concentration of N≥1 cm-a and liquid water content of L≥0.001 g m-a can be used to define sea fogs in this area. The type of fog droplet size distribution of the sea fog events was mostly monotonically-decreasing, with the spectrum width always being 〉20 μm. The significant temporal variation of N was due in large part to the number concentration variation of fog droplets with radius 〈3 μm. A strong collection process appeared when droplet spectrum width was 〉10 μm, which subsequently led to the sudden increase of droplet spectrmn width. The doln- inant physical process during the sea fog events was activation with subsequent condensational growth or reversible evaporation processes, but turbulent mixing also played an important role. The collection process occurred, but was not vital.
