气候变化领域集成服务门户(CCPortal): Highly supercooled riming and unusual triple-frequency radar signatures over McMurdo Station, Antarctica

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DOI	10.5194/acp-22-12467-2022
	Highly supercooled riming and unusual triple-frequency radar signatures over McMurdo Station, Antarctica
	Tridon, Frederic; Silber, Israel; Battaglia, Alessandro; Kneifel, Stefan; Fridlind, Ann; Kalogeras, Petros; Dhillon, Ranvir
发表日期	2022
ISSN	1680-7316
EISSN	1680-7324
起始页码	12467
结束页码	12491
卷号	22 期号:18 页码:25
英文摘要	Riming of ice crystals by supercooled water droplets is an efficient ice growth process, but its basic properties are still poorly known. While it has been shown to contribute significantly to surface precipitation at mid-latitudes, little is known about its occurrence at high latitudes. In Antarctica, two competing effects can influence the occurrence of riming: (i) the scarcity of supercooled liquid water clouds due to the extremely low tropospheric temperatures and (ii) the low aerosol concentration, which may lead to the formation of fewer and larger supercooled drops potentially resulting in an enhanced riming efficiency. In this work, by exploiting the deployment of an unprecedented number of multiwavelength remote sensing systems (including triple-frequency radar measurements) in West Antarctica, during the Atmospheric Radiation Measurements West Antarctic Radiation Experiment (AWARE) field campaign, we evaluate the riming incidence at McMurdo Station and find that riming occurs at much lower temperatures when compared to previous results in the mid-latitudes. This suggests the possible occurrence of a common atmospheric state over Antarctica that includes a rather stable atmosphere inhibiting turbulent mixing, and a high riming efficiency driven by large cloud droplets. We then focus on a peculiar case study featuring a persistent layer with a particularly pronounced riming signature in triple-frequency radar data but only a relatively modest amount of supercooled liquid water. In-depth analysis of the radar observations suggests that such signatures can only be explained by the combined effects of moderately rimed aggregates or similarly shaped florid polycrystals and a narrow particle size distribution (PSD). Simulations of this case study performed with a one-dimensional bin model indicate that similar triple-frequency radar observations can be reproduced when narrow PSDs are simulated. Such narrow PSDs can in turn be explained by two key factors: (i) the presence of a shallow homogeneous droplet or humidified aerosol freezing layer aloft seeding an underlying supercooled liquid layer, and (ii) the absence of turbulent mixing throughout a stable polar atmosphere that sustains narrow PSDs, as hydrometeors grow from the nucleation region aloft to ice particles of several millimeters in size, by vapor deposition and then riming.
学科领域	Environmental Sciences; Meteorology & Atmospheric Sciences
语种	英语
WOS研究方向	Environmental Sciences & Ecology ; Meteorology & Atmospheric Sciences
WOS记录号	WOS:000857513100001
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/273635
作者单位	University of Cologne; Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Pennsylvania State University - University Park; Polytechnic University of Turin; University of Leicester; University of Munich; National Aeronautics & Space Administration (NASA); NASA Goddard Space Flight Center
推荐引用方式 GB/T 7714	Tridon, Frederic,Silber, Israel,Battaglia, Alessandro,et al. Highly supercooled riming and unusual triple-frequency radar signatures over McMurdo Station, Antarctica[J],2022,22(18):25.
APA	Tridon, Frederic.,Silber, Israel.,Battaglia, Alessandro.,Kneifel, Stefan.,Fridlind, Ann.,...&Dhillon, Ranvir.(2022).Highly supercooled riming and unusual triple-frequency radar signatures over McMurdo Station, Antarctica.ATMOSPHERIC CHEMISTRY AND PHYSICS,22(18),25.
MLA	Tridon, Frederic,et al."Highly supercooled riming and unusual triple-frequency radar signatures over McMurdo Station, Antarctica".ATMOSPHERIC CHEMISTRY AND PHYSICS 22.18(2022):25.