THE LATEST ASSESSMENT FOR THE REPROCESSED GDR PRODUCT OF HY-2A ALTIMETER

This paper is aimed to assess the accuracy of HY-2A altimetry system. To further improve the accuracy and performance of HY-2A observed SSHs, several new treatments including 4 parameters maximum likelihood estimation (MLE4) retracking for Ku and C band, non-parameter sea state bias (NPSSB) model, and reprocessed dual-frequency altimeter ionospheric correction are included. The evaluation from dual-crossover comparison of the fully reprocessed level-2 sensor geophysical dataset records (SGDRs) data suggests that the algorithm and model improvements mentioned above give rise to remarkable promotion to the accuracy of the forthcoming version GDRs. In this study we conclude that the standard deviation of 5.79 cm is achieved from crossover comparison between HY-2A and Jason-2 sea surface height (SSHs), suggesting a promising situation of HY-2A altimetry datasets.