The Performance of Altimeter Waveform Retrackers at Lake Baikal
Résumé
At each of five fixed locations along the ground tracks of JASON-1 and ENVISAT, a repeat-track analysis of 1-Hz sea surface height (SSH) data has been conducted to assess the performance of wavefoim retrackers over Lake Baikal in Siberia, Russia. This simple analysis of time series at each point location is needed to minimize the effect of the range correction artifacts in current Geophysical Data Record (GDR) data products of radar altimeters in in-land areas. Using the retracked data available in the GDRs as the baseline, two retrackers are evaluated in terms of the number of valid data points produced and the degree of agreement with in-situ data of water level record. The threshold retrackers that are based on the amplitude of the robust OCOG algorithm (Offset Center of Gravity) are found to perform the best in Lake Baikal.