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DOI	10.5194/acp-19-14967-2019
	Evaluation of hygroscopic cloud seeding in liquid-water clouds: A feasibility study
	Wang F.; Li Z.; Jiang Q.; Wang G.; Jia S.; Duan J.; Zhou Y.
发表日期	2019
ISSN	16807316
起始页码	14967
结束页码	14977
卷号	19 期号:23
英文摘要	An airborne cloud seeding experiment was conducted over the eastern coast of Zhejiang, China, on 4 September 2016 during a major international event held in Hangzhou. In an attempt to reduce the likelihood of rainfall onset, a major airborne experiment for weather modification took place by seeding hygroscopic agents to warm clouds to reduce cloud droplet size. The effectiveness of seeding is examined, mainly for stratiform clouds with patchy small convective cells. A radar-domain-index (RDI) algorithm was proposed to analyze the seeding effect. The threshold strategy and the tracking radar echo by correlation (TREC) technique was applied in the domain selection. Factors analyzed include echo reflectivity parameters such as the mean and maximum echo intensity, the anomaly percentage of the grid number of effective echoes, the fractional contribution to the total reflectivities, and the vertically integrated liquid (VIL) water content during and after the seeding process. About 12 min after seeding ended, the composite reflectivity of seeded clouds decreased to a minimum (< 10 dBz) and the VIL of seeded clouds was ĝ1/40.2 kg m-3. The echo top height dropped to ĝ1/43.5 km, and the surface echoes were also weakened. By contrast, there was no significant variation in these echo parameters for the surrounding non-seeded clouds. The seeded cell appeared to have the shortest life cycle, as revealed by applying the cloud-cluster tracking method. The airborne Cloud Droplet Probe (CDP) measured cloud number concentration, effective diameter, and liquid water content, which gradually increased after the start of cloud seeding. This is probably caused by the hygroscopic growth of agent particles and collision-coalescence of small cloud droplets. However, these parameters sampled at ĝ1/440 min after seeding decreased significantly, which is probably due to the excessive seeding agents generating a competition for cloud water and thus suppressing cloud development and precipitation. Overall, the physical phenomenon was captured in this study, but a more quantitative in-depth analysis of the underlying principle is needed. © Author(s) 2019. This work is distributed under the Creative Commons Attribution 4.0 License.
语种	英语
scopus关键词	algorithm; cloud microphysics; cloud seeding; convective system; droplet; feasibility study; hygroscopicity; size distribution; stratiform cloud; water content; China; Hangzhou; Zhejiang
来源期刊	Atmospheric Chemistry and Physics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/143984
作者单位	Key Laboratory for Cloud Physics, Chinese Academy of Meteorological Sciences, Beijing, 100081, China; State Key Laboratory of Earth Surface Processes and Resource Ecology, College of Global Change and Earth System Science, Beijing Normal University, Beijing, 100875, China; Department of Atmospheric and Oceanic Science, University of Maryland, College Park, MD 20742, United States; National Meteorological Center, Beijing, 100081, China; State Key Laboratory of Severe Weather, Chinese Academy of Meteorological Science, Beijing, 100081, China; China Huayun Group, Beijing, 100081, China
推荐引用方式 GB/T 7714	Wang F.,Li Z.,Jiang Q.,et al. Evaluation of hygroscopic cloud seeding in liquid-water clouds: A feasibility study[J],2019,19(23).
APA	Wang F..,Li Z..,Jiang Q..,Wang G..,Jia S..,...&Zhou Y..(2019).Evaluation of hygroscopic cloud seeding in liquid-water clouds: A feasibility study.Atmospheric Chemistry and Physics,19(23).
MLA	Wang F.,et al."Evaluation of hygroscopic cloud seeding in liquid-water clouds: A feasibility study".Atmospheric Chemistry and Physics 19.23(2019).