Abstract:Waveform modification provides a possibility to further improve the quality of coastal altimetry data. Using the Jason-1 SGDR data, the shortcoming of Tseng’s modification method is pointed out. We propose an improved modification algorithm by revising the strategy of selecting reference waveforms and determining weights for amending outliers. Test results show the improved method can avoid the deformation of waveform leading edge caused by Tseng’s method, and effectively increases the precision of coastal sea surface heights.