气候变化领域集成服务门户(CCPortal): Three years of sea ice freeboard, snow depth, and ice thickness of the weddell sea from operation icebridge and cryosat-2

CCPortal

DOI	10.5194/tc-12-2789-2018
	Three years of sea ice freeboard, snow depth, and ice thickness of the weddell sea from operation icebridge and cryosat-2
	Kwok R.; Kacimi S.
发表日期	2018
ISSN	19940416
卷号	12 期号:8
英文摘要	We examine the variability of sea ice freeboard, snow depth, and ice thickness in three years (2011, 2014, and 2016) of repeat surveys of an IceBridge (OIB) transect across the Weddell Sea. Averaged over this transect, ice thickness ranges from 2.40±1.07 (2011) to 2.60±1.15m (2014) and snow depth from 35.8±11.5 (2016) to 43.6±10.2cm (2014), suggesting a highly variable but broadly thicker ice cover compared to that inferred from drilling and ship-based measurements. Spatially, snow depth and ice thickness are higher in the more deformed ice of the western Weddell. The impact of undersampling the thin end of the snow depth distribution on the regional statistics, due to the resolution of the snow radar, is assessed. Radar freeboards (uncompensated for snow thickness) from CryoSat-2 (CS-2) sampled along the same transect are consistently higher (by up to 8cm) than those computed using OIB data. This suggests radar scattering that originates above the snow-ice interface, possibly due to salinity in the basal layer of the snow column. Consequently, sea ice thicknesses computed using snow depth estimates solely from differencing OIB and CS-2 freeboards (without snow radar) are therefore generally higher; mean differences in sea ice thickness along a transect are up to ∼ 0.6m higher (in 2014). This analysis is relevant to the use of differences between ICESat-2 and CS-2 freeboards to estimate snow depth for ice thickness calculations. Our analysis also suggests that, even with these expected biases, this is an improvement over the assumption that snow depth is equal to the total freeboard, with which the underestimation of thickness could be up to a meter. Importantly, better characterization of the source of these biases is critical for obtaining improved estimates and understanding the limits of retrievals of Weddell Sea ice thickness from satellite altimeters. © 2018 Copernicus GmbH. All rights reserved.
学科领域	altimeter; CryoSat; ice cover; ice thickness; ocean island basalt; radar; salinity; satellite data; sea ice; snow; vertical distribution; Southern Ocean; Weddell Sea
语种	英语
scopus关键词	altimeter; CryoSat; ice cover; ice thickness; ocean island basalt; radar; salinity; satellite data; sea ice; snow; vertical distribution; Southern Ocean; Weddell Sea
来源期刊	Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/119078
作者单位	Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States
推荐引用方式 GB/T 7714	Kwok R.,Kacimi S.. Three years of sea ice freeboard, snow depth, and ice thickness of the weddell sea from operation icebridge and cryosat-2[J],2018,12(8).
APA	Kwok R.,&Kacimi S..(2018).Three years of sea ice freeboard, snow depth, and ice thickness of the weddell sea from operation icebridge and cryosat-2.Cryosphere,12(8).
MLA	Kwok R.,et al."Three years of sea ice freeboard, snow depth, and ice thickness of the weddell sea from operation icebridge and cryosat-2".Cryosphere 12.8(2018).