气候变化领域集成服务门户(CCPortal): Microphysics and dynamics of snowfall associated with a warm conveyor belt over Korea

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DOI	10.5194/acp-20-7373-2020
	Microphysics and dynamics of snowfall associated with a warm conveyor belt over Korea
	Gehring J.; Oertel A.; Vignon E.; Jullien N.; Besic N.; Berne A.
发表日期	2020
ISSN	1680-7316
起始页码	7373
结束页码	7392
卷号	20 期号:12
英文摘要	On 28 February 2018, 57span classCombining double low line"inline-formula"mm/span of precipitation associated with a warm conveyor belt (WCB) fell within 21span classCombining double low line"inline-formula"h/span over South Korea. To investigate how the large-scale circulation influenced the microphysics of this intense precipitation event, we used radar measurements, snowflake photographs and radiosounding data from the International Collaborative Experiments for Pyeongchang 2018 Olympic and Paralympic Winter Games (ICE-POP 2018). The WCB was identified with trajectories computed with analysis wind fields from the Integrated Forecast System global atmospheric model. The WCB was collocated with a zone of enhanced wind speed of up to 45span classCombining double low line"inline-formula"m s-1/span at 6500span classCombining double low line"inline-formula"m/spana.s.l., as measured by a radiosonde and a Doppler radar. Supercooled liquid water (SLW) with concentrations exceeding 0.2span classCombining double low line"inline-formula"g kg-1/span was produced during the rapid ascent within the WCB. During the most intense precipitation period, vertical profiles of polarimetric radar variables show a peak and subsequent decrease in differential reflectivity as aggregation starts. Below the peak in differential reflectivity, the specific differential phase shift continues to increase, indicating early riming of oblate crystals and secondary ice generation. We hypothesise that the SLW produced in the WCB led to intense riming. Moreover, embedded updraughts in the WCB and turbulence at its lower boundary enhanced aggregation by increasing the probability of collisions between particles. This suggests that both aggregation and riming occurred prominently in this WCB. This case study shows how the large-scale atmospheric flow of a WCB provides ideal conditions for rapid precipitation growth involving SLW production, riming and aggregation. Future microphysical studies should also investigate the synoptic conditions to understand how observed processes in clouds are related to large-scale circulation. © 2020 Copernicus GmbH. All rights reserved.
语种	英语
scopus关键词	atmospheric circulation; atmospheric dynamics; atmospheric modeling; cloud microphysics; formation mechanism; precipitation assessment; probability; rime; snow; synoptic meteorology; wind field; wind velocity; South Korea
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/141257
作者单位	Environmental Remote Sensing Laboratory (LTE), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland; Institute for Atmospheric and Climate Science (IAC), Eidgenössische Technische Hochschule Zürich (ETH), Zurich, Switzerland; Department of Geosciences, University of Fribourg, Fribourg, Switzerland; Centre Météorologie Radar, Météo France, Toulouse, France
推荐引用方式 GB/T 7714	Gehring J.,Oertel A.,Vignon E.,et al. Microphysics and dynamics of snowfall associated with a warm conveyor belt over Korea[J],2020,20(12).
APA	Gehring J.,Oertel A.,Vignon E.,Jullien N.,Besic N.,&Berne A..(2020).Microphysics and dynamics of snowfall associated with a warm conveyor belt over Korea.Atmospheric Chemistry and Physics,20(12).
MLA	Gehring J.,et al."Microphysics and dynamics of snowfall associated with a warm conveyor belt over Korea".Atmospheric Chemistry and Physics 20.12(2020).