Details

Autor(en) / Beteiligte

• Nilsson, Johan
• Vallelonga, Paul
• Simonsen, Sebastian B.
• Sørensen, Louise Sandberg
• Forsberg, René
• Dahl-Jensen, Dorthe
• Hirabayashi, Motohiro
• Goto-Azuma, Kumiko
• Hvidberg, Christine S.
• Kjær, Helle A.
• Satow, Kazuhide

Titel

Greenland 2012 melt event effects on CryoSat-2 radar altimetry

Ist Teil von

• Geophysical research letters, 2015-05, Vol.42 (10), p.3919-3926

Ort / Verlag

Washington: Blackwell Publishing Ltd

Erscheinungsjahr

2015

Link zum Volltext

Quelle

Wiley Online Library All Journals

Beschreibungen/Notizen

• CryoSat‐2 data are used to study elevation changes over an area in the interior part of the Greenland Ice Sheet during the extreme melt event in July 2012. The penetration of the radar signal into dry snow depends heavily on the snow stratigraphy, and the rapid formation of refrozen ice layers can bias the surface elevations obtained from radar altimetry. We investigate the change in CryoSat‐2 waveforms and elevation estimates over the melt event and interpret the findings by comparing in situ surface and snow pit observations from the North Greenland Eemian Ice Drilling Project camp. The investigation shows a major transition of scattering properties around the area, and an apparent elevation increase of 56 ± 26 cm is observed in reprocessed CryoSat‐2 data. We suggest that this jump in elevation can be explained by the formation of a refrozen melt layer that raised the reflective surface, introducing a positive elevation bias. Key Points CryoSat‐2 radar altimetry was applied to 2012 Greenland melt event Surface melt introduces an elevation bias by changing snow scattering properties In situ observations confirm a significant bias in retrieved surface height