气候变化领域集成服务门户(CCPortal): The 2018 North Greenland polynya observed by a newly introduced merged optical and passive microwave sea-ice concentration dataset

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DOI	10.5194/tc-13-2051-2019
	The 2018 North Greenland polynya observed by a newly introduced merged optical and passive microwave sea-ice concentration dataset
	Ludwig V.; Spreen G.; Haas C.; Istomina L.; Kauker F.; Murashkin D.
发表日期	2019
ISSN	19940416
EISSN	13
起始页码	2051
结束页码	2073
卷号	13 期号:7
英文摘要	Observations of sea-ice concentration are available from satellites year-round and almost weatherindependently using passive microwave radiometers at resolutions down to 5 km. Thermal infrared radiometers provide data with a resolution of 1 km but only under cloud-free conditions. We use the best of the two satellite measurements and merge thermal infrared and passive microwave sea-ice concentrations. This yields a merged sea-ice concentration product combining the gap-free spatial coverage of the passive microwave sea-ice concentration and the 1 km resolution of the thermal infrared sea-ice concentration. The benefit of the merged product is demonstrated by observations of a polynya which opened north of Greenland in February 2018. We find that the merged sea-ice concentration product resolves leads at sea-ice concentrations between 60% and 90 %. They are not resolved by the coarser passive microwave sea-ice concentration product. The benefit of the merged product is most pronounced during the formation of the polynya. Next, the environmental conditions during the polynya event are analysed. The polynya was caused by unusual southerly winds during which the sea ice drifted northward instead of southward as usual. The daily displacement was 50% stronger than normal. The polynya was associated with a warm-air intrusion caused by a high-pressure system over the Eurasian Arctic. Surface air temperatures were slightly below 0 °C and thus more than 20 -C higher than normal. Two estimates of thermodynamic sea-ice growth yield sea-ice thicknesses of 60 and 65 cm at the end of March in the area opened by the polynya. This differed from airborne sea-ice thickness measurements, indicating that sea-ice growth processes in the polynya are complicated by rafting and ridging. A sea-ice volume of 33 km3 was produced thermodynamically. © 2019 Author(s). This work is distributed under the Creative Commons Attribution 4.0 License.
学科领域	air temperature; concentration (composition); data set; high pressure system; ice thickness; introduced species; microwave radiation; polynya; satellite data; sea ice; thermodynamics; Arctic; Arctic; Eurasia; Greenland
语种	英语
scopus关键词	air temperature; concentration (composition); data set; high pressure system; ice thickness; introduced species; microwave radiation; polynya; satellite data; sea ice; thermodynamics; Arctic; Arctic; Eurasia; Greenland
来源期刊	The Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/118851
作者单位	Institute for Environmental Physics, University of Bremen, Otto-Hahn-Allee 1, Bremen, 28359, Germany; Alfred Wegener Institute for Polar and Marine Research, Am Handelshafen 12, Bremerhaven, 27570, Germany; O.A.Sys - Ocean Atmosphere Systems GmbH, Tewessteg 4, Hamburg, 20249, Germany
推荐引用方式 GB/T 7714	Ludwig V.,Spreen G.,Haas C.,et al. The 2018 North Greenland polynya observed by a newly introduced merged optical and passive microwave sea-ice concentration dataset[J],2019,13(7).
APA	Ludwig V.,Spreen G.,Haas C.,Istomina L.,Kauker F.,&Murashkin D..(2019).The 2018 North Greenland polynya observed by a newly introduced merged optical and passive microwave sea-ice concentration dataset.The Cryosphere,13(7).
MLA	Ludwig V.,et al."The 2018 North Greenland polynya observed by a newly introduced merged optical and passive microwave sea-ice concentration dataset".The Cryosphere 13.7(2019).