Kong Ya-Wen, Sheng Li-Fang, Liu Qian, Li Xiu-Zhen
College of Oceanic and Atmospheric Sciences, Ocean University of China, Qingdao 266100, China.
Key Laboratory of Physical Oceanography, Ministry of Education, Ocean University of China, Qingdao 266100, China.
Huan Jing Ke Xue. 2016 Jul 8;37(7):2443-2452. doi: 10.13227/j.hjkx.2016.07.005.
The shipboard measurements of aerosol number concentration from August 28th to October 13th, 2012 were conducted to analyze the characteristics of temporal-spatial distribution and number size distribution of marine aerosol in the South China Sea. The impact of meteorological condition on the marine aerosol was also analyzed in this paper. The result showed that the temporal-spatial distribution and number size distribution of marine aerosol were influenced by the backward trajectory of the air masses and the time they spent over the sea, and the meteorological conditions in the local sea area such as wind speed, wind direction, temperature, relative humidity and cloud cover. In terms of temporal-spatial distribution of marine aerosol in the South China Sea, the aerosol in the sea areas under the influence of continental air mass concentration showed much higher concentration than that in the clean maritime air mass (2300 cm vs. 1200 cm). During the ship observation, three kinds of number size distribution of marine aerosol were found and classified:polluted type, marine type 1 and marine type 2 (clean). All the distributions had a similar sub-micron mode and a similar coarse mode. The marine type 2 (clean) had the same distribution shape as polluted type except that the value of concentration was much lower. The sub-micron peak of marine type 1 appeared near 0.08 μm and its concentration was significantly higher than that of marine type 2 (clean). Non-precipitating clouds as well as abundant moisture contributed to the growth of ultrafine particles to the size of accumulation mode aerosol (0.05-0.12 μm). Number concentration of particles in this range showed weak positive correlation with wind speed since wind can enhance the efficiency of sea-air exchange and accelerate the release of gas precursors of sulfate aerosol to the atmosphere. The concentration of coarse particles ranging from 0.5-6 μm in diameter strongly depended on the wind speed, and the correlation coefficient reached a value of 0.7.
2012年8月28日至10月13日进行了南海海域气溶胶数浓度的船上测量，以分析南海海洋气溶胶的时空分布特征和粒径分布。本文还分析了气象条件对海洋气溶胶的影响。结果表明，海洋气溶胶的时空分布和粒径分布受气团后向轨迹及其在海上停留时间的影响，以及当地海域的气象条件，如风速、风向、温度、相对湿度和云量。就南海海洋气溶胶的时空分布而言，受大陆气团影响的海域气溶胶浓度远高于清洁海洋气团下的海域（2300个/cm³对1200个/cm³）。在船舶观测期间，发现并分类了三种海洋气溶胶粒径分布：污染型、海洋型1和海洋型2（清洁型）。所有分布都有相似的亚微米模态和相似的粗模态。海洋型2（清洁型）与污染型具有相同的分布形状，只是浓度值低得多。海洋型1的亚微米峰值出现在0.08μm附近，其浓度明显高于海洋型2（清洁型）。非降水云以及丰富的水汽有助于超细颗粒生长到积聚模态气溶胶的大小（0.05-0.12μm）。该范围内颗粒的数浓度与风速呈弱正相关，因为风可以提高海气交换效率，并加速硫酸盐气溶胶的气体前体向大气中的释放。直径在0.5-6μm范围内的粗颗粒浓度强烈依赖于风速，相关系数达到0.7。
