We present a regional validation exercise in the German Bight of Level 2 Altimetry Data acquired by the CryoSat-2 mission in SAR (Synthetic Aperture Radar) Mode against in-situ data and model results in the time interval 2011- 2012. The in-situ data are from a network of tide gauges, GNSS stations and offshore platforms in open sea and coastal zone. The validated parameters are the sea surface height above the ellipsoid (SSH) and the significant sea wave height (SWH). Data in SAR mode are processed to produce both pseudo pulse-limited (PLRM) and Delay-Doppler processed SAR waveform data. The first are provided via the RADS database, the second by the EOP-SER Altimetry Team at ESRIN, which re-tracks the Delay-Doppler processed SAR waveform data using the SAMOSA re-tracker. Biases in SSH and SWH occurring in SAR mode are analysed to tune up the SAR re-tracking scheme. As performance metrics to measure the quality of the results, scatter plots, cross-correlations, standard deviations, and biases between PLRM and SAR processing and altimetry and in-situ measurements are presented. The comparison of the SWH derived from SAR and PLRM with model data present a good agreement for waves in the range of 1-2 meters and larger departures for higher waves. The agreement with in-situ data is good at the open sea platform FINO3 and slightly higher with SAR than with RADS data. The comparison between altimetric and in-situ SSH shows a good agreement and no bias for the SAR and PLRM processed data. SAR data are less noisy than PLRM data as expected.
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