Jianqiu Gao , Zhujie Li , Junxia Li , Gang Wang , Chang Chen , Songwei He , Zhiyuan Shu , Shaoyu Hou , Junjun Lin
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引用次数: 0
Abstract
To study the distribution characteristics of aerosols and clouds in South China under the influence of typical weather systems such as the southern trough, this paper analyzed the distribution and sources of aerosols and cloud droplets based on six flight observations conducted in Guangdong during the spring of 2024. The results indicated that aerosol number concentrations often peak above cloud tops or in the regions between two cloud layers. The average aerosol number concentration outside the clouds at high altitudes (2000–4100 m) ranged from 501 to 1617 cm−3, while in the near-surface layer it was 970 to 2168 cm−3, with an effective diameter averaging 0.27 to 0.5 μm. The concentration inside the clouds significantly decreased, and the diameter increased. The aerosol particle spectrum displayed a bimodal distribution, with peaks at 0.15 μm and 0.29 μm. The number concentration of particles smaller than 0.3 μm within the clouds declined, while the proportion of particles larger than 0.5 μm increased. The cloud droplet spectrum displayed a multimodal distribution, with the main peak occurring at a diameter of around 5 μm and secondary peaks found at diameters in the range of 10 to 16 μm. As the cloud layer thickened, the droplet spectrum broadened, large droplet concentrations increased, and small droplet concentrations decreased. Under the influence of non-precipitating stratus clouds in South China, the average aerosol scavenging efficiency was 0.47. The mean cloud droplet number concentration, liquid water content, and effective diameter were 67.3 cm−3, 0.02 g·m−3, and 9.4 μm, respectively. Long-range transport originating from South Asia and Southeast Asia is suggested as a potential contributing factor to the elevated high-altitude aerosol concentrations. The research findings deepen the understanding of cloud and aerosol microphysical characteristics in the South China region. This contributes to the evaluation of climate models and provides guidance for artificial weather modification operations.
期刊介绍:
The journal publishes scientific papers (research papers, review articles, letters and notes) dealing with the part of the atmosphere where meteorological events occur. Attention is given to all processes extending from the earth surface to the tropopause, but special emphasis continues to be devoted to the physics of clouds, mesoscale meteorology and air pollution, i.e. atmospheric aerosols; microphysical processes; cloud dynamics and thermodynamics; numerical simulation, climatology, climate change and weather modification.