Gravity field from cryosat-2 sar altimetry: the merits of the empirical primary peak retrackers

SAR lead and ocean data from Cryosat-2 is processed using waveform retracking for estimation of gravity fields in the Arctic Ocean. The retrackers proposed in this work are based on the combination of the OCOG (Offset Centre of Gravity) and Threshold methods with Primary Peak extraction. These proposed retrackers are used to construct sea surface height anomalies for the Arctic. Next, gravity fields are computed from the sea surface height anomalies. The gravity fields are computed for various retrackers: traditional Threshold, traditional OCOG, Primary Peak OCOG, Primary Peak Threshold and the ESA retracker. It was concluded through this work that Primary Peak retrackers result in more accurate gravity fields as compared to other retrackers for SAR lead data in the Arctic.