A new digital elevation model of Antarctica derived from CryoSat-2 altimetry

• Published in: The Cryosphere
• Main Authors: Slater, Thomas, Shepherd, Andrew, McMillan, Malcolm, Muir, Alan, Gilbert, Lin, Hogg, Anna E., Konrad, Hannes, Parrinello, Tommaso
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus Publications 2018
• Subjects: article; Verlagsveröffentlichung; Antarctic; The Antarctic; Antarc*; Antarctica; Ice Sheet; Ice Shelves; The Cryosphere
• Online Access: https://doi.org/10.5194/tc-12-1551-2018; https://noa.gwlb.de/receive/cop_mods_00006196; https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00006153/tc-12-1551-2018.pdf; https://tc.copernicus.org/articles/12/1551/2018/tc-12-1551-2018.pdf

We present a new digital elevation model (DEM) of the Antarctic ice sheet and ice shelves based on 2.5×108 observations recorded by the CryoSat-2 satellite radar altimeter between July 2010 and July 2016. The DEM is formed from spatio-temporal fits to elevation measurements accumulated within 1, 2, and 5 km grid cells, and is posted at the modal resolution of 1 km. Altogether, 94 % of the grounded ice sheet and 98 % of the floating ice shelves are observed, and the remaining grid cells north of 88∘ S are interpolated using ordinary kriging. The median and root mean square difference between the DEM and 2.3×107 airborne laser altimeter measurements acquired during NASA Operation IceBridge campaigns are −0.30 and 13.50 m, respectively. The DEM uncertainty rises in regions of high slope, especially where elevation measurements were acquired in low-resolution mode; taking this into account, we estimate the average accuracy to be 9.5 m – a value that is comparable to or better than that of other models derived from satellite radar and laser altimetry.