Tidal data of Tanggu marine environment monitoring stations for 59 years （1950-2008） was processed by using harmonic analysis, harmonic constants curves were discussed. And by using FFT spectral analysis periodicity...Tidal data of Tanggu marine environment monitoring stations for 59 years （1950-2008） was processed by using harmonic analysis, harmonic constants curves were discussed. And by using FFT spectral analysis periodicity and causation of its harmonic constants were analyzed. Alter astronomic tide signal was eliminated, residual water level was decomposed by using FFT spectral analysis, and then we got the periodic variation of mean residual water level over the past 50 years and discussed mean sea level changing trends of Tianjin offshore. The results show that variety of amplitude of M2 tidal constituent reveals 20 years, 4-6 years, 2-3-year periods, and it was obviously influenced by engineering construction since reform and opening age. Residual water level fluctuations reveal 20 years, 5-6 years, 2-3 years and 1 year periods. Sea level of Tianjin offshore displays a progressive ascending trend with rate about 3.4mm/a, which was influenced mainly by sea level rise and land subsidence.展开更多
TOPEX/POSEIDON altimeter data from October 1992 to June 2002 are used to calculate the global barotropic M2 tidal currents using long-term tidal harmonic analysis. The tides calculated agree well with ADCP data obtain...TOPEX/POSEIDON altimeter data from October 1992 to June 2002 are used to calculate the global barotropic M2 tidal currents using long-term tidal harmonic analysis. The tides calculated agree well with ADCP data obtained from the South China Sea （SCS）. The maximum tide velocities along the semi-major axis and semi-minor axis can be computed from the tidal ellipse. The global distribution of M2 internal tide vertical energy flux from the sea bottom is calculated based on a linear internal wave generation model. The global vertical energy flux of M2 internal tide is 0.96 TW, with 0.36 TW in the Pacific, 0.31 TW in the Atlantic and 0.29 TW in the Indian Ocean, obtained in this study. The total horizontal energy flux of M2 internal tide radiating into the open ocean from the lateral boundaries is 0.13 TW, with 0.06 TW in the Pacific, 0.04TW in the Atlantic, and 0.03 TW in the Indian Ocean. The result shows that the principal lunar semi-diurnal tide Me provides enough energy to maintain the large-scale thermohaline circulation of the ocean.展开更多
Objective： To study which items need the formulation of national standards and which standards should be first formulated. Methods： Apply the method of the questionnaire survey to collect data, and the statistical a...Objective： To study which items need the formulation of national standards and which standards should be first formulated. Methods： Apply the method of the questionnaire survey to collect data, and the statistical analysis adopt the frequency and weighted average method. Results： Propose the items of acupuncture and moxibustion which need the urgent formulation of standards and the sequence in the formulation of standard items. Conclusion： Provid important bases for the follow-up report of national standard items and avoid temporary formulation of standards without plan .展开更多
文摘Tidal data of Tanggu marine environment monitoring stations for 59 years （1950-2008） was processed by using harmonic analysis, harmonic constants curves were discussed. And by using FFT spectral analysis periodicity and causation of its harmonic constants were analyzed. Alter astronomic tide signal was eliminated, residual water level was decomposed by using FFT spectral analysis, and then we got the periodic variation of mean residual water level over the past 50 years and discussed mean sea level changing trends of Tianjin offshore. The results show that variety of amplitude of M2 tidal constituent reveals 20 years, 4-6 years, 2-3-year periods, and it was obviously influenced by engineering construction since reform and opening age. Residual water level fluctuations reveal 20 years, 5-6 years, 2-3 years and 1 year periods. Sea level of Tianjin offshore displays a progressive ascending trend with rate about 3.4mm/a, which was influenced mainly by sea level rise and land subsidence.
基金Supported by the National Basic Research Program of China (973 Program, No. 2005CB422303)the International Cooperation Program (No. 2004DFB02700)+1 种基金the National Natural Science Foundation of China (No. 40552002)The TOPEX/POSEIDON data are provided by Physical Oceanography Distributed Active Archive Center (PO DACC)
文摘TOPEX/POSEIDON altimeter data from October 1992 to June 2002 are used to calculate the global barotropic M2 tidal currents using long-term tidal harmonic analysis. The tides calculated agree well with ADCP data obtained from the South China Sea （SCS）. The maximum tide velocities along the semi-major axis and semi-minor axis can be computed from the tidal ellipse. The global distribution of M2 internal tide vertical energy flux from the sea bottom is calculated based on a linear internal wave generation model. The global vertical energy flux of M2 internal tide is 0.96 TW, with 0.36 TW in the Pacific, 0.31 TW in the Atlantic and 0.29 TW in the Indian Ocean, obtained in this study. The total horizontal energy flux of M2 internal tide radiating into the open ocean from the lateral boundaries is 0.13 TW, with 0.06 TW in the Pacific, 0.04TW in the Atlantic, and 0.03 TW in the Indian Ocean. The result shows that the principal lunar semi-diurnal tide Me provides enough energy to maintain the large-scale thermohaline circulation of the ocean.
基金TCM project supported by the National Program of Science and Technology Development (2006BA121B01)
文摘Objective： To study which items need the formulation of national standards and which standards should be first formulated. Methods： Apply the method of the questionnaire survey to collect data, and the statistical analysis adopt the frequency and weighted average method. Results： Propose the items of acupuncture and moxibustion which need the urgent formulation of standards and the sequence in the formulation of standard items. Conclusion： Provid important bases for the follow-up report of national standard items and avoid temporary formulation of standards without plan .
