Impacts of CCN on droplet spectra of rain and fog during high pollution days
FANG Sha-sha1, HAN Yong-xiang1, WANG Jin2, ZHANG Zhi3
1. Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science and Technology, Nanjing 210044, China;
2. Guizhou institute of Mountainous Climate and Environment, Guiyang 550005, China;
3. Yunnan Meteorological Service Center, Kunming 650034, China
Based on observational data obtained by a cloud condensation nuclei (CCN) counter, a fog droplet spectrometer and an raindrop disdrometer, together with ground-based meteorological data, the impacts of atmospheric pollutants on CCN and the droplet spectra of rain and fog were analyzed. Results showed that: the CCN concentration in Weining remained very high during the observation period, and the average CCN number concentration were 2884, 8003, 10470 and 11685cm-3 at S=0.2%, 0.4%, 0.6% and 0.8%, respectively, which were comparable with those obtained in polluted cities; the CCN concentration displayed a significant daily variation, peaking at 12:00, 16:00 and 20:00, respectively, which was relate to human activities, power plants emissions, turbulent exchange and meteorological conditions; the CCN spectra can be fitted by the expression N=CSk, with the fitting parameter C=14288cm-3 and k=0.8, indicating that the CCN spectra can be classified as a typical continental type. The precipitation characteristics of the stratiform cloud in Weining provided macro synoptic situations, and high CCN concentrations were an important microphysical condition for narrow droplet spectra of rain and fog.
方莎莎, 韩永翔, 王瑾, 张智. 高污染下云凝结核对雨、雾滴谱的影响[J]. 中国环境科学, 2016, 36(9): 2585-2590.
FANG Sha-sha, HAN Yong-xiang, WANG Jin, ZHANG Zhi. Impacts of CCN on droplet spectra of rain and fog during high pollution days. CHINA ENVIRONMENTAL SCIENCECE, 2016, 36(9): 2585-2590.
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