Toward improved sea ice freeboard observation with SAR altimetry using the physical retracker SAMOSA+

Since 2010, the CryoSat-2 satellite mission has enabled to largely improve sea ice freeboard estimations. But due complexity of radar echoes over ice, retrieval from altimetry still presents some errors and biases that further limit potential these observations for climate studies or assimilation into models. Various methods have been explored, producing a large range In this study, we analyze main steps computation developed as part Cryo-SeaNice Project. The objective is quantify impacts each processing method identify optimal strategies estimations SAR measurements. We consider two options: Hamming Window (HW) with Zero-Padding (ZP), 2 retrackers: Threshold First Maximum Retracker Algorithm (TFMRA) based on heuristic measurements SAMOSA+ retracker declined model analysis surface back-scatter. Four solutions are generated combinations options (HW ZP only) types retrackers. addition, an alternative filter out side-lobes presented. different approaches estimate quantified comparisons Operation Ice Bridge (OIB) Beaufort Gyre Exploration project (BGEP) in situ data. Our results show provides more precise This new time-series available CTOH website. also identified both Finally, present using simpler threshold but correction account roughness calibrated against SAMOSA+.