The difference analysis of physical-mechanical properties of muddy sediments is made in the central South Yellow Sea and the Zhe-Min（Zhejiang Province to Fujian Province of China） coastal area. The results show that...The difference analysis of physical-mechanical properties of muddy sediments is made in the central South Yellow Sea and the Zhe-Min（Zhejiang Province to Fujian Province of China） coastal area. The results show that sediments in the two regions are both dominated by mud. There are perfect negative power function correlations between the water content and the density, the compression coefficient and the compression modulus; a good positive power function correlation between the liquid limit and the plastic limit, a perfect positive linear correlation between the water content and the void ratio, and a perfect polynomial function correlation between the miniature vane shear strength and the pocket penetration resistance. In general, compared with sediments in the Zhe-Min coastal area, sediments in the central South Yellow Sea possess high water content, high void ratio,low density, high plasticity, high compressibility, low shear strength. The causes of the differences between physical-mechanical properties of sediments are analyzed from the topographic features, material sources,hydrodynamic conditions, deposition rate, and material composition. Compared with the Zhe-Min coastal area,the central South Yellow Sea is far from the Mainland and low-lying; has poor hydrodynamic condition; the materials diffused to the area are less and dominated by fine clay, have the high content of smectite and organic matters. These factors lead to sediments of the central South Yellow Sea has the higher water content, the higher plasticity, the lower density, and the lower strength than sediments in the Zhe-Min coastal area.展开更多
A 10-year(2003–2012)hindcast was conducted to study the wave field in the Zhe-Min coastal area(Key Area OE-W2)located off Zhejiang and Fujian provinces of China.Forced by the wind field from a weather research and fo...A 10-year(2003–2012)hindcast was conducted to study the wave field in the Zhe-Min coastal area(Key Area OE-W2)located off Zhejiang and Fujian provinces of China.Forced by the wind field from a weather research and forecasting model(WRF),high-resolution wave modelling using the SWAN was carried out in the study area.The simulated wave fields show a good agreement with observations.Using the simulation results,we conducted statistical analysis of wave power density in terms of spatial distribution and temporal variation.The effective duration of wave energy in the sea area was discussed,and the stability of wave energy was evaluated using the coefficient of variation of wave power density.Results indicate that the wave energy resource in the study area was about 4.11×10^(6) kW.The distribution of wave energy tends to increase from the north(off Zhejiang coast)to the south(off Fujian coast),and from near-shore area to the open sea.The sea areas with wave power density greater than 2 kW/m are mostly distributed seaward of the 10-m isobath,and the contours of the wave power density are almost parallel to the shoreline.The sea areas around the islands that are far from the mainland are rich in wave energy,usually more than 6 kW/m,and therefore are of obvious advantages in planning wave energy development and utilization.The effective duration of wave energy in the offshore area shows an increasing trend from north(off Zhejiang coast)to south(off Fujian coast),with values of∼3500 h in the north and∼4450 h in the south.The coefficient of variation of wave energy in this region is mostly in the range of 1.5–3.0,and gradually decreases from the north to the south,suggesting that the wave energy in the south is more stable than that in the north.展开更多
In conjunction with synchronous remotely sensed winds and sea surface temperature （SST）, the spatiotemporal features of the Zhe-Min coastal current （ZMCC）, especially responses of the ZMCC adjacent to Pingtan Isla...In conjunction with synchronous remotely sensed winds and sea surface temperature （SST）, the spatiotemporal features of the Zhe-Min coastal current （ZMCC）, especially responses of the ZMCC adjacent to Pingtan Island （PT） to the wintertime mon- soon relaxation in 2006 and corresponding mechanism are investigated based on the field observations. In situ data are ac- quired from Conductivity-Temperature-Depth （CTD） cruise and Bottom-Mounted Moorings （BMM）, which are conducted during a comprehensive survey for the Chinese Offshore Investigation and Assessment Project in winter 2006. It is revealed that the ZMCC is well mixed vertically in winter 2006. The ZMCC （〈14℃） recedes during the relaxation of the wintertime monsoon and is accompanied by the enhanced northward shift of the warm, saline Taiwan Strait Mixed Water （TSMW, higher than 14~C and is constituted by the Taiwan Strait Warm Water and the Kuroshio Branch Water）. And greatly enhanced south- ward intrusion of the ZMCC can be detected when the wintertime monsoon restores. Correspondingly, the thermal interface bounded by the ZMCC and the TSMW moves in the northwest/southeast direction, leading to periodic warm/cold reversals of the near-seabed temperature adjacent to the PT. By EOF （Empirical Orthogonal Function） analysis of the large-scale wind fields and wavelet power spectrum analysis of the water level, ocean current and the near-seabed temperature, responses of the ZMCC off the PT to wintertime monsoon relaxation are suggested to be attributed mainly to the southward propagating coast- ally trapped waves triggered by the impeding atmospheric fronts. As a result, ocean current and near-seabed temperature demonstrate significant quasi-5 d and quasi-10 d subtidal oscillations. By contrast, the onshore/offshore water accumulation resulted from Ekman advection driven by the local winds has minor contributions.展开更多
基金The NSFC-Shandong Joint Fund for Marine Science Research Centers under contract No.U150640007the Natural Science Foundation of Shandong Province of China under contract No.BS2015HZ009the National Natural Science Foundation of China under contract No.41506071
文摘The difference analysis of physical-mechanical properties of muddy sediments is made in the central South Yellow Sea and the Zhe-Min（Zhejiang Province to Fujian Province of China） coastal area. The results show that sediments in the two regions are both dominated by mud. There are perfect negative power function correlations between the water content and the density, the compression coefficient and the compression modulus; a good positive power function correlation between the liquid limit and the plastic limit, a perfect positive linear correlation between the water content and the void ratio, and a perfect polynomial function correlation between the miniature vane shear strength and the pocket penetration resistance. In general, compared with sediments in the Zhe-Min coastal area, sediments in the central South Yellow Sea possess high water content, high void ratio,low density, high plasticity, high compressibility, low shear strength. The causes of the differences between physical-mechanical properties of sediments are analyzed from the topographic features, material sources,hydrodynamic conditions, deposition rate, and material composition. Compared with the Zhe-Min coastal area,the central South Yellow Sea is far from the Mainland and low-lying; has poor hydrodynamic condition; the materials diffused to the area are less and dominated by fine clay, have the high content of smectite and organic matters. These factors lead to sediments of the central South Yellow Sea has the higher water content, the higher plasticity, the lower density, and the lower strength than sediments in the Zhe-Min coastal area.
基金The National Key R&D Program of China under contract No.2018YFB1501901the Zhejiang Provincial Natural Science Foundation of China under contract No.LY21D060003the Project of State Key Laboratory of Satellite Ocean Environment Dynamics,Second Institute of Oceanography,Ministry of Natural Resources,under contract Nos SOEDZZ2103 and SOEDZZ2003.
文摘A 10-year(2003–2012)hindcast was conducted to study the wave field in the Zhe-Min coastal area(Key Area OE-W2)located off Zhejiang and Fujian provinces of China.Forced by the wind field from a weather research and forecasting model(WRF),high-resolution wave modelling using the SWAN was carried out in the study area.The simulated wave fields show a good agreement with observations.Using the simulation results,we conducted statistical analysis of wave power density in terms of spatial distribution and temporal variation.The effective duration of wave energy in the sea area was discussed,and the stability of wave energy was evaluated using the coefficient of variation of wave power density.Results indicate that the wave energy resource in the study area was about 4.11×10^(6) kW.The distribution of wave energy tends to increase from the north(off Zhejiang coast)to the south(off Fujian coast),and from near-shore area to the open sea.The sea areas with wave power density greater than 2 kW/m are mostly distributed seaward of the 10-m isobath,and the contours of the wave power density are almost parallel to the shoreline.The sea areas around the islands that are far from the mainland are rich in wave energy,usually more than 6 kW/m,and therefore are of obvious advantages in planning wave energy development and utilization.The effective duration of wave energy in the offshore area shows an increasing trend from north(off Zhejiang coast)to south(off Fujian coast),with values of∼3500 h in the north and∼4450 h in the south.The coefficient of variation of wave energy in this region is mostly in the range of 1.5–3.0,and gradually decreases from the north to the south,suggesting that the wave energy in the south is more stable than that in the north.
基金supported by National Natural Science Foundation of China(Grant Nos.41176031 and 40806013)Chinese Offshore Physical Oceanography and Marine Meteorology Investigation and Assessment Project(Grant No.908-ZC-I-01)National Basic Research Program of China(Grant No:.2011CB403504).
文摘In conjunction with synchronous remotely sensed winds and sea surface temperature （SST）, the spatiotemporal features of the Zhe-Min coastal current （ZMCC）, especially responses of the ZMCC adjacent to Pingtan Island （PT） to the wintertime mon- soon relaxation in 2006 and corresponding mechanism are investigated based on the field observations. In situ data are ac- quired from Conductivity-Temperature-Depth （CTD） cruise and Bottom-Mounted Moorings （BMM）, which are conducted during a comprehensive survey for the Chinese Offshore Investigation and Assessment Project in winter 2006. It is revealed that the ZMCC is well mixed vertically in winter 2006. The ZMCC （〈14℃） recedes during the relaxation of the wintertime monsoon and is accompanied by the enhanced northward shift of the warm, saline Taiwan Strait Mixed Water （TSMW, higher than 14~C and is constituted by the Taiwan Strait Warm Water and the Kuroshio Branch Water）. And greatly enhanced south- ward intrusion of the ZMCC can be detected when the wintertime monsoon restores. Correspondingly, the thermal interface bounded by the ZMCC and the TSMW moves in the northwest/southeast direction, leading to periodic warm/cold reversals of the near-seabed temperature adjacent to the PT. By EOF （Empirical Orthogonal Function） analysis of the large-scale wind fields and wavelet power spectrum analysis of the water level, ocean current and the near-seabed temperature, responses of the ZMCC off the PT to wintertime monsoon relaxation are suggested to be attributed mainly to the southward propagating coast- ally trapped waves triggered by the impeding atmospheric fronts. As a result, ocean current and near-seabed temperature demonstrate significant quasi-5 d and quasi-10 d subtidal oscillations. By contrast, the onshore/offshore water accumulation resulted from Ekman advection driven by the local winds has minor contributions.
