Tidal analysis refinedly from the data of satallites with exact repeat orbit
To mitigate the influence of observational noise in satellite altimetry sea surface height data on tidal signal extraction,a preprocessing method based on segmented fitting for sea surface height data is proposed.Simultaneously,to improve the accuracy of tidal parameter acquisition in nearshore and strong current areas and considering the variable characteristics of sea surface height in such regions,a joint adjustment model for tidal parameters and sea surface height variations based on segmented mean sea surface height setting is proposed to detect the sea surface changes in strong current areas.The results indicate that by applying the improved along-track analysis method and long-term T/P and Jason series altimetry satellite data,through statistical analysis of cross-point discrepancies,the error in the comprehensive tidal height prediction of eight major tidal constituents has been reduced to 2.04 cm globally and achieved an accuracy level of 3～4 cm in three global strong current areas and their diffusion areas.The research findings can provide a higher quality dataset of tidal harmonic constants for refining tidal models.Simultaneously,high-frequency sea surface height variation sequences in strong current areas and their diffusion bodies are detected,which can be used to study the temporal processes and patterns of strong currents.
万方数据
维普
