Validation of an Empirical Subwaveform Retracking Strategy for SAR Altimetry

The sea level retrievals from the latest generation of radar altimeters (the SAR altimeters) are still challenging in coastal zone and areas covered by ice require a dedicated fitting (retracking) strategy for waveforms. In framework European Space Agency’s Baltic + Sea Level (ESA SEAL) project, an empirical retracking (ALES SAR), including state bias correction, has been designed to improve observations Sea, characterised jagged coastline seasonal coverage, without compromising quality open ocean data. this work, performances ALES validated against in-situ data Sea. Moreover, variance, crossover differences power spectral density evaluated on global scale. results show that comparable ones obtained using physical-based retrackers, with relevant advantages terms quantity