Specific processing
For open ocean, the treatment of the signal and the corrections to be applied are well known and the height measurements of the surface are very precise. Near coasts and for inland waters, the precision decreases, mainly due to models and corrections not well adapted and also due to echo signals which are modified by the presence of land. However measurements are present and contain useful information. To get closer to the coasts or over continental water bodies with a better coverage and data with good quality, waveform perturbations have to be analysed, retrackers have to be specialized, threshold have to be modified, correction have to be adapted.