An algorithm （differential mode） is presented for the improvement of harmonic tidal analysis along T/P tracks, in which the differences between the observed sea surface heights at adjacent points are taken as observ...An algorithm （differential mode） is presented for the improvement of harmonic tidal analysis along T/P tracks, in which the differences between the observed sea surface heights at adjacent points are taken as observations. Also, the observation equations are constrained with the results of the crossover analysis; the parameter estimations are performed at 0.1° latitude intervals by the least squares. Cycle 10 to 330 T/P altimeter data covering the China Sea and the Northwest Pacific Ocean （2°-50° N,105°-150° E） are adopted for a refined along-track harmonic tidal analysis, and harmonic constants of 12 constituents in 8 474 points are obtained, which indicates that the algorithm can efficiently remove non-tidal effects in the altimeter observations, and improve the precision of tide parameters. Moreover, parameters along altimetry tracks represent a smoother distribution than those obtained by traditional algorithms. The root mean squares of the fitting errors between the tidal height model and the observations reduce from 11 cm to 1.3 cm.展开更多
The sea surface height oscillation with a quasi-four-month period （SSHO4） along continental slope in the northern South China Sea （NSCS） is detected using satellite altimeter data and an ocean model simulation. Th...The sea surface height oscillation with a quasi-four-month period （SSHO4） along continental slope in the northern South China Sea （NSCS） is detected using satellite altimeter data and an ocean model simulation. The SSHO4 is at southwest of Dongsha Island, and is characterized by a wavelength of-600 km and a southwestward phase speed of-0.1 m/s. Crossing the climatological background SST front, geostrophic currents corresponding to the SSHO4 generally induce sea surface temperature （SST） ＂tongues＂ during January-March. The cold and warm SST tongues appear southwest of cyclonic and anticyclonic eddies, respectively. The distance between the warm and cold SST tongues is about half the wavelength of the SSHO4. The geostrophic currents play an important role in lateral mixing, as manifested by the SST tongue phenomena in the NSCS.展开更多
基金Supported by the National Natural Science Foundation of China （No. 40671161） and the Open Research Fund Program of the Key Laboratory of Geospace Environment and Geodesy, Ministry of Education, China（No.1469990324233-03-04）.
文摘An algorithm （differential mode） is presented for the improvement of harmonic tidal analysis along T/P tracks, in which the differences between the observed sea surface heights at adjacent points are taken as observations. Also, the observation equations are constrained with the results of the crossover analysis; the parameter estimations are performed at 0.1° latitude intervals by the least squares. Cycle 10 to 330 T/P altimeter data covering the China Sea and the Northwest Pacific Ocean （2°-50° N,105°-150° E） are adopted for a refined along-track harmonic tidal analysis, and harmonic constants of 12 constituents in 8 474 points are obtained, which indicates that the algorithm can efficiently remove non-tidal effects in the altimeter observations, and improve the precision of tide parameters. Moreover, parameters along altimetry tracks represent a smoother distribution than those obtained by traditional algorithms. The root mean squares of the fitting errors between the tidal height model and the observations reduce from 11 cm to 1.3 cm.
基金Supported by the Ministry of Science and Technology of China(National Basic Research Program of China(No.2012CB955602))the National Key Program for Developing Basic Science(No.2010CB428904)+1 种基金the National Natural Science Foundation of China(No.40830106)a China Postdoctoral Science Foundation Funded Project(No.20100471573)
文摘The sea surface height oscillation with a quasi-four-month period （SSHO4） along continental slope in the northern South China Sea （NSCS） is detected using satellite altimeter data and an ocean model simulation. The SSHO4 is at southwest of Dongsha Island, and is characterized by a wavelength of-600 km and a southwestward phase speed of-0.1 m/s. Crossing the climatological background SST front, geostrophic currents corresponding to the SSHO4 generally induce sea surface temperature （SST） ＂tongues＂ during January-March. The cold and warm SST tongues appear southwest of cyclonic and anticyclonic eddies, respectively. The distance between the warm and cold SST tongues is about half the wavelength of the SSHO4. The geostrophic currents play an important role in lateral mixing, as manifested by the SST tongue phenomena in the NSCS.
