气候变化领域集成服务门户(CCPortal): Improved retrieval of land ice topography from CryoSat-2 data and its impact for volume-change estimation of the Greenland Ice Sheet

CCPortal

DOI	10.5194/tc-10-2953-2016
	Improved retrieval of land ice topography from CryoSat-2 data and its impact for volume-change estimation of the Greenland Ice Sheet
	Nilsson J.; Gardner A.; Sørensen L.S.; Forsberg R.
发表日期	2016
ISSN	19940416
卷号	10 期号:6
英文摘要	A new methodology for retrieval of glacier and ice sheet elevations and elevation changes from CryoSat-2 data is presented. Surface elevations and elevation changes determined using this approach show significant improvements over ESA's publicly available CryoSat-2 elevation product (L2 Baseline-B). The results are compared to near-coincident airborne laser altimetry from NASA's Operation IceBridge and seasonal height amplitudes from the Ice, Cloud, and Elevation Satellite (ICESat). Applying this methodology to CryoSat-2 data collected in interferometric synthetic aperture mode (SIN) over the high-relief regions of the Greenland Ice Sheet we find an improvement in the root-mean-square error (RMSE) of 27 and 40% compared to ESA's L2 product in the derived elevation and elevation changes, respectively. In the interior part of the ice sheet, where CryoSat-2 operates in low-resolution mode (LRM), we find an improvement in the RMSE of 68 and 55% in the derived elevation and elevation changes, respectively. There is also an 86% improvement in the magnitude of the seasonal amplitudes when compared to amplitudes derived from ICESat data. These results indicate that the new methodology provides improved tracking of the snow/ice surface with lower sensitivity to changes in near-surface dielectric properties. To demonstrate the utility of the new processing methodology we produce elevations, elevation changes, and total volume changes from CryoSat-2 data for the Greenland Ice Sheet during the period January 2011 to January 2015. We find that the Greenland Ice Sheet decreased in volume at a rate of 289 ± 20km3 a-1, with high interannual variability and spatial heterogeneity in rates of loss. This rate is 65km3 a-1 more negative than rates determined from ESA's L2 product, highlighting the importance of CryoSat-2 processing methodologies. © Author(s) 2016.
学科领域	airborne sensing; annual variation; CryoSat; dielectric property; estimation method; GLAS; heterogeneity; ice sheet; ICESat; interferometry; methodology; sensitivity analysis; spatial analysis; topography; volume change; Arctic; Greenland; Greenland Ice Sheet
语种	英语
scopus关键词	airborne sensing; annual variation; CryoSat; dielectric property; estimation method; GLAS; heterogeneity; ice sheet; ICESat; interferometry; methodology; sensitivity analysis; spatial analysis; topography; volume change; Arctic; Greenland; Greenland Ice Sheet
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/119533
作者单位	Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, United States; DTU Space, National Space Institute, Technical University of Denmark, Kgs. Lyngby, 2800, Denmark
推荐引用方式 GB/T 7714	Nilsson J.,Gardner A.,Sørensen L.S.,et al. Improved retrieval of land ice topography from CryoSat-2 data and its impact for volume-change estimation of the Greenland Ice Sheet[J],2016,10(6).
APA	Nilsson J.,Gardner A.,Sørensen L.S.,&Forsberg R..(2016).Improved retrieval of land ice topography from CryoSat-2 data and its impact for volume-change estimation of the Greenland Ice Sheet.Cryosphere,10(6).
MLA	Nilsson J.,et al."Improved retrieval of land ice topography from CryoSat-2 data and its impact for volume-change estimation of the Greenland Ice Sheet".Cryosphere 10.6(2016).