10.24400/527896/A03-2022.3465
Luciana Fenoglio
Luciana
Fenoglio
University of Bonn, Germany
Hakan Uyanik
Hakan
Uyanik
University of Bonn, Germany
Bernd Uebbing
Bernd
Uebbing
University of Bonn, Germany
Sophie Stolzenberger
Sophie
Stolzenberger
University of Bonn, Germany
Buchhaupt Christopher
Buchhaupt
Christopher
Universit of Maryland, USA
Jürgen Kusche
Jürgen
Kusche
University of Bonn, Germany
Evaluation of coastal water level products in SAR mode
CNES
2022
2022 Ocean Surface Topography Science Team Meeting
Coastal zones, estuaries and inland waters are among the environments most affected by anthropogenic impact and climate change and are multi-risk due to coastline retreat, flooding and pollution. Accurate knowledge of water height is of major importance to analyze and understand causes and drivers of changes and to plan protection measures. Satellite delay doppler altimetry (DDA) provides improved results compared to conventional altimetry (CA). Goal of this study is the evaluation of the state of art and enhanced dedicated coastal and inland retrackers to understand their limitation, plan improved processing and new missions.
The project HYDROCOASTAL brings together coastal and inland water zone measurements by SAR altimeter. Several retrackers, dedicated to one or both zones are applied in the processing of CryoSat-2 and Sentinel-3A/B altimeter data.
The University of Bonn contributes to the Hydrocoastal Project with the enhanced retracking and validation efforts. The Spatio-Temporal Altimeter Retracker for SAR altimetry (STARS) is an enhancement of the STAR retracker for low resolution mode (LRM) and uses the functional waveform model Signal model Involving Numerical Convolution for SAR (SINCS) to retrack the Delay Doppler waveforms.
The geophysical parameters estimated by retracking are evaluated in each region from all available retrackers. At Uni-Bonn the validation activities focus on the German Bight and Baltic Sea coastal region and include the Elbe estuary. The goal is to carry out a characterization of the product performance with estimation of the data accuracy. A cross-validation analysis of the new SAR products is performed against other altimeter products, model data and insitu data. The study area has been used for the validation of radar altimeter data in open ocean and near the shore in previous work.
The study presents and discusses the validation results based on the validation matrix which has been agreed with the project partners. The resulting statistics is compared in few cases with the statistics output from the in-house validation strategy matrix.