Haidong Pan , Junchuan Sun , Tengfei Xu , Zexun Wei
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引用次数: 0
Abstract
Exact tidal information is essential for multifarious human activities in the global ocean. Satellite altimeters especially Topex/Poseidon (T/P) and Jason series play fundamental roles in improving our understanding of global tides. Compared to T/P-Jason series, other satellite altimeters such as Geosat Follow-On (GFO) have been rarely used in tidal studies mainly due to their unfavorable aliasing features for tidal estimates. Classical harmonic analysis requires 12-year GFO records to fully resolve eight major tidal constituents while the longest GFO data is only 8-year. As a result, it is challenging for classical harmonic analysis to derive reliable tidal estimates from short GFO records. In this study, a modified tidal harmonic analysis algorithm based on the credo of smoothness (i.e. MHACS) is introduced to extract ocean tides from GFO records in the Bohai Sea. Via utilizing the inherent natural links between main constituents, MHACS breaks the constraint of the Rayleigh criterion and effectively solves tidal aliasing problems in GFO records. Practical experiments indicate that GFO-derived tidal constants via MHACS have high consistencies with the tidal theory and satellite-based EOT20 tidal model. Spatially-averaged vector difference between the EOT20 model and GFO results in the Bohai Sea is only 2.12 cm (eight major constituents averaged). Moreover, except for GFO, MHACS also has the potential to be applied to sun-synchronous satellites such as Envisat, Sentinel series, and Haiyang series.
期刊介绍:
Continental Shelf Research publishes articles dealing with the biological, chemical, geological and physical oceanography of the shallow marine environment, from coastal and estuarine waters out to the shelf break. The continental shelf is a critical environment within the land-ocean continuum, and many processes, functions and problems in the continental shelf are driven by terrestrial inputs transported through the rivers and estuaries to the coastal and continental shelf areas. Manuscripts that deal with these topics must make a clear link to the continental shelf. Examples of research areas include:
Physical sedimentology and geomorphology
Geochemistry of the coastal ocean (inorganic and organic)
Marine environment and anthropogenic effects
Interaction of physical dynamics with natural and manmade shoreline features
Benthic, phytoplankton and zooplankton ecology
Coastal water and sediment quality, and ecosystem health
Benthic-pelagic coupling (physical and biogeochemical)
Interactions between physical dynamics (waves, currents, mixing, etc.) and biogeochemical cycles
Estuarine, coastal and shelf sea modelling and process studies.