The inflow angle of tropical cyclones (TC) is generally neglected in numerical studies of ocean surface waves induced by TC. In this study, the impacts of TC inflow angle on ocean surface waves were investigated usi...The inflow angle of tropical cyclones (TC) is generally neglected in numerical studies of ocean surface waves induced by TC. In this study, the impacts of TC inflow angle on ocean surface waves were investigated using a high-resolution wave model. Six numerical experiments were conducted to examine, in detail, thc effects of inflow angle on mean wave parameters and the spectrum of wave directions. A comparison of the waves simulated in these experiments shows that inflow angle significantly modifies TC-induced ocean surface waves. As the inflow angle increases, the asymmetric axis of the significant wave height (SWH) field shifts 30° clockwise, and the maximum SWH moves from the front-right to the rear-right quadrant. Inflow angle also affects other mean wave parameters, especially in the rear-left quadrant, such as the mean wave direction, the mean wavelength, and the peak direction. Inflow angle is a key factor in wave models for the reproduction of double-peak or multi-peak patterns in the spectrum of wave directions. Sensitivity experiments also show that the simulation with a 40° inflow angle is the closest to that of the NOAA statistical SLOSH inflow angle. This suggests that 40° can be used as the inflow angle in future TC-induced ocean surface wave simulations when SLOSH or observed inflow angles are not available.展开更多
The wave characteristics affecting coastal sediment transport include wave height, wave period and breaking wave direction. Wave height is a critical factor in determining the amount of sediment transport in the coast...The wave characteristics affecting coastal sediment transport include wave height, wave period and breaking wave direction. Wave height is a critical factor in determining the amount of sediment transport in the coastal area. The force of sediment transport is much more intense under breaking waves than under non-breaking waves. Breaking waves exhibit various patterns, principal- ly depending on the incident wave steepness and the beach slope. Based on the equations of con- servation of mass, momentum and energy, a theoretical model for wave deformation in and outside the surf zone was obtained, which is used to calculate the wave shoaling, wave set-up and set- down and wave height distributions in and outside the surf zone. The analysis and comparison were made about the breaking point location and the wave height decay caused by the wave breaking and the bottom friction. Flume experiments relating to the spilling wave height distribution across the surf zone were conducted to verify the theoretical model. Advanced wave maker, data sampling de- vices and data processing system were utilized in the flume experiments with a slope covered by sands of different diameters to facilitate the observation and research on the wave transformation and breaking. The agreement between the theoretical and experimental results is good.展开更多
A synoptic snapshot in this study is made for the East Cape Eddy (ECE) basedon the World Ocean Circulation Experiment (WOCE) P14C Hydrographic Section and Shipboard ADCPvelocity vector data collected in September 1992...A synoptic snapshot in this study is made for the East Cape Eddy (ECE) basedon the World Ocean Circulation Experiment (WOCE) P14C Hydrographic Section and Shipboard ADCPvelocity vector data collected in September 1992. The ECE is an anticyclonic eddy, barotropicallystructured and centered at 33.64°S and 176.21°E, with warm and salinous-cored subsurface water.The radius of the eddy is of the order O (110 km) and the maximum circumferential velocity is O (40cm s^(-1)); as a result, the relative vorticity is estimated to be O (7 x 10^(-6)s^(-1)). Due to theexistence of the ECE, the mixed layer north of New Zealand becomes deeper, reaching a depth of 300m in the austral winter. The ECE plays an important role in the formation and distribution of theSubtropical Mode Water (STMW) over a considerable area in the South Pacific.展开更多
基金Supported by the National Natural Science Foundation of China(No. 40706008)the Open Research Program of the Chinese Academy Sciences Key Laboratory of Tropical Marine Environmental Dynamics (No. LED0606)+1 种基金the Shandong Province Natural Science Foundation (No. Z2008E02)the National High Technology Research and Development Program of China (863 Program) (No.2008AA09A402)
文摘The inflow angle of tropical cyclones (TC) is generally neglected in numerical studies of ocean surface waves induced by TC. In this study, the impacts of TC inflow angle on ocean surface waves were investigated using a high-resolution wave model. Six numerical experiments were conducted to examine, in detail, thc effects of inflow angle on mean wave parameters and the spectrum of wave directions. A comparison of the waves simulated in these experiments shows that inflow angle significantly modifies TC-induced ocean surface waves. As the inflow angle increases, the asymmetric axis of the significant wave height (SWH) field shifts 30° clockwise, and the maximum SWH moves from the front-right to the rear-right quadrant. Inflow angle also affects other mean wave parameters, especially in the rear-left quadrant, such as the mean wave direction, the mean wavelength, and the peak direction. Inflow angle is a key factor in wave models for the reproduction of double-peak or multi-peak patterns in the spectrum of wave directions. Sensitivity experiments also show that the simulation with a 40° inflow angle is the closest to that of the NOAA statistical SLOSH inflow angle. This suggests that 40° can be used as the inflow angle in future TC-induced ocean surface wave simulations when SLOSH or observed inflow angles are not available.
基金Supported by Doctoral Fund of Education Ministry of China ( No. 20010056033) , National Natural Science Foundation of China(No. 10202003, No. 50479015) ,and National Science Fund for Distinguished Young Scholars(No. 03QMH1408).
文摘The wave characteristics affecting coastal sediment transport include wave height, wave period and breaking wave direction. Wave height is a critical factor in determining the amount of sediment transport in the coastal area. The force of sediment transport is much more intense under breaking waves than under non-breaking waves. Breaking waves exhibit various patterns, principal- ly depending on the incident wave steepness and the beach slope. Based on the equations of con- servation of mass, momentum and energy, a theoretical model for wave deformation in and outside the surf zone was obtained, which is used to calculate the wave shoaling, wave set-up and set- down and wave height distributions in and outside the surf zone. The analysis and comparison were made about the breaking point location and the wave height decay caused by the wave breaking and the bottom friction. Flume experiments relating to the spilling wave height distribution across the surf zone were conducted to verify the theoretical model. Advanced wave maker, data sampling de- vices and data processing system were utilized in the flume experiments with a slope covered by sands of different diameters to facilitate the observation and research on the wave transformation and breaking. The agreement between the theoretical and experimental results is good.
文摘A synoptic snapshot in this study is made for the East Cape Eddy (ECE) basedon the World Ocean Circulation Experiment (WOCE) P14C Hydrographic Section and Shipboard ADCPvelocity vector data collected in September 1992. The ECE is an anticyclonic eddy, barotropicallystructured and centered at 33.64°S and 176.21°E, with warm and salinous-cored subsurface water.The radius of the eddy is of the order O (110 km) and the maximum circumferential velocity is O (40cm s^(-1)); as a result, the relative vorticity is estimated to be O (7 x 10^(-6)s^(-1)). Due to theexistence of the ECE, the mixed layer north of New Zealand becomes deeper, reaching a depth of 300m in the austral winter. The ECE plays an important role in the formation and distribution of theSubtropical Mode Water (STMW) over a considerable area in the South Pacific.