THE GERMAN BIGHT: PREPARING FOR SENTINEL-3 WITH A CROSS-VALIDATION OF SAR AND PLRM CRYOSAT-2 ALTIMETER DATA

摘要

As preparatory work for Sentinel-3, we retrieve thernthree geophysical parameters: sea surface height (SSH),rnsignificant wave height (SWH) and wind speed at 10rnmeters height (U10) from CryoSat-2 data in ourrnvalidation region in North Sea.rnThe CryoSat-2 SAR echoes are processed with arncoherent and an incoherent processing to generate SARrnand PLRM data respectively. We derive precision andrnaccuracy at 1 Hz in open ocean, at distances larger thanrn10 kilometres from the coast. A cross-validation of thernSAR and PLRM altimeter data is performed torninvestigate the differences between the products. LookrnUp Tables (LUT) are applied in both schemes to correctrnfor approximations applied in both retrackingrnprocedures. Additionally a numerical retracker is usedrnin PLRM. The results are validated against in-situ andrnmodel data. The analysis is performed for a period ofrnfour years, from July 2010 to May 2014.rnThe regional cross-validation analysis confirms therngood consistency between PLRM and SAR data. UsingrnLUT the agreement for the sea wave heights increasesrnby 10%.