气候变化领域集成服务门户(CCPortal): Antarctic clouds; supercooled liquid water and mixed phase; investigated with DARDAR: Geographical and seasonal variations

CCPortal

DOI	10.5194/acp-19-6771-2019
	Antarctic clouds; supercooled liquid water and mixed phase; investigated with DARDAR: Geographical and seasonal variations
	Listowski C.; Delanoë J.; Kirchgaessner A.; Lachlan-Cope T.; King J.
发表日期	2019
ISSN	16807316
起始页码	6771
结束页码	6808
卷号	19 期号:10
英文摘要	Antarctic tropospheric clouds are investigated using the DARDAR (raDAR/liDAR)-MASK products between 60 and 82° S. The cloud fraction (occurrence frequency) is divided into the supercooled liquid-water-containing cloud (SLC) fraction and its complementary part called the all-ice cloud fraction. A further distinction is made between SLC involving ice (mixed-phase clouds, MPC) or not (USLC, for unglaciated SLC). The low-level (< 3 km above surface level) SLC fraction is larger over seas (20 %-60 %), where it varies according to sea ice fraction, than over continental regions (0 %-35 %). The total SLC fraction is much larger over West Antarctica (10 %-40 %) than it is over the Antarctic Plateau (0 %-10 %). In East Antarctica the total SLC fraction-in summer for instance-decreases sharply polewards with increasing surface height (decreasing temperatures) from 40% at the coast to < 5% at 82° S on the plateau. The geographical distribution of the continental total all-ice fraction is shaped by the interaction of the main low-pressure systems surrounding the continent and the orography, with little association with the sea ice fraction. Opportunistic comparisons with published ground-based supercooled liquidwater observations at the South Pole in 2009 are made with our SLC fractions at 82° S in terms of seasonal variability, showing good agreement. We demonstrate that the largest impact of sea ice on the low-level SLC fraction (and mostly through the MPC) occurs in autumn and winter (22 % and 18 % absolute decrease in the fraction between open water and sea ice-covered regions, respectively), while it is almost null in summer and intermediate in spring (11 %). Monthly variability of the MPC fraction over seas shows a maximum at the end of summer and a minimum in winter. Conversely, the USLC fraction has a maximum at the beginning of summer. However, monthly evolutions of MPC and USLC fractions do not differ on the continent. This suggests a seasonality in the glaciation process in marine liquid-bearing clouds. From the literature, we identify the pattern of the monthly evolution of the MPC fraction as being similar to that of the aerosols in coastal regions, which is related to marine biological activity. Marine bioaerosols are known to be efficient ice-nucleating particles (INPs). The emission of these INPs into the atmosphere from open waters would add to the temperature and sea ice fraction seasonalities as factors explaining the MPC fraction monthly evolution. © 2019 Author(s).
语种	英语
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/144391
作者单位	LATMOS/IPSL, UVSQ Université Paris-Saclay, UPMC Univ. Paris 06 Sorbonne Universités, CNRS, Guyancourt, France; British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge, CB3 OET, United Kingdom
推荐引用方式 GB/T 7714	Listowski C.,Delanoë J.,Kirchgaessner A.,et al. Antarctic clouds; supercooled liquid water and mixed phase; investigated with DARDAR: Geographical and seasonal variations[J],2019,19(10).
APA	Listowski C.,Delanoë J.,Kirchgaessner A.,Lachlan-Cope T.,&King J..(2019).Antarctic clouds; supercooled liquid water and mixed phase; investigated with DARDAR: Geographical and seasonal variations.Atmospheric Chemistry and Physics,19(10).
MLA	Listowski C.,et al."Antarctic clouds; supercooled liquid water and mixed phase; investigated with DARDAR: Geographical and seasonal variations".Atmospheric Chemistry and Physics 19.10(2019).