By using a coordinate transformation,an exact solution of internal tides is obtained when the bot- tom slope is linear and the V(?)is(?)la frequency is constant.Consequently the dispersion relations of free waves are ...By using a coordinate transformation,an exact solution of internal tides is obtained when the bot- tom slope is linear and the V(?)is(?)la frequency is constant.Consequently the dispersion relations of free waves are presented.Compared with Baines solution,the solution derived here is more consistent with展开更多
A two-dimensional spectral-difference mode (with vorticity and density equations) of internal tides isdeveloped for studying the genration and propagration of internal tides generated at the continentalshelf/slope. In...A two-dimensional spectral-difference mode (with vorticity and density equations) of internal tides isdeveloped for studying the genration and propagration of internal tides generated at the continentalshelf/slope. In general, internal tides propagate seaward in deep sea regions and shoreward on the shelf,and are dissipated rapidly. When the Vaisala frequency decreases vertically, waves may be mostly limited to thecontinental slope region. in deep sea region, motions may have either boam-like structure or modal structure,depending on the stratification strerigth and structure, whereas a modal structure may always exist onthe shelf. Waves show strong bottom intensification on the slope when strong stratification exists on thebottom. The barotropic tidal advection may affed the temporal character of internal tides at thecontinental slope, shelf break and shelf regions. but may have little influence on the energy density and energy flux of internal tides. ln the case of strong stratification, waverforms展开更多
By using a coordinate transformation, an exact solution of internal tides with sub-inertial frequency isobtained when the bottom slope is linear and the Vaisala frequency is constant. Accordingly thedispersion relatio...By using a coordinate transformation, an exact solution of internal tides with sub-inertial frequency isobtained when the bottom slope is linear and the Vaisala frequency is constant. Accordingly thedispersion relations of free waves are presented. This solution is suitable for general coastal low-frequencybaroclinic waves with zero alongshore wavenumber.展开更多
By using part of CTD data collected at 2°S, 155° E during the fall cruise of TOGA project in 1992, themultifractal characters of temperature finestructures are investigated. The absolute temperature gradient...By using part of CTD data collected at 2°S, 155° E during the fall cruise of TOGA project in 1992, themultifractal characters of temperature finestructures are investigated. The absolute temperature gradients are supposedto be multifractal and their moments are computed by conventional box-counting method. It is found that these moments have power dependence on the box size. This power dependence has two different scaling regimes, called Sregime and I-regime resistively, with different scaling exponents. This is consistent with the combined effects of internal waves and boxing. Accordingly, the generalized fractal dimensions (Renyi dimension) of temperature gradientsare derived. A nonlinear curve of the scaling exponents suggest a possible multifractal approach of the temperatureshear. In fact, both regimes can be approximated by Besicovitch- Cantor model, respectively, by suitably chosenmoduel parameters. A phenomenological model is developed on the basis of this two-regime mechanism. The model iscompared with field data and good agreement is achieved.展开更多
基金National Education Committee Foundation Programs 9142305 and 9342305National Natural Science Foundation Program 49376257National Special Research Program 85-927-05-03
文摘By using a coordinate transformation,an exact solution of internal tides is obtained when the bot- tom slope is linear and the V(?)is(?)la frequency is constant.Consequently the dispersion relations of free waves are presented.Compared with Baines solution,the solution derived here is more consistent with
基金National Education Committee Foundation Program(9142305)National Science Foundation Program(49376257)
文摘A two-dimensional spectral-difference mode (with vorticity and density equations) of internal tides isdeveloped for studying the genration and propagration of internal tides generated at the continentalshelf/slope. In general, internal tides propagate seaward in deep sea regions and shoreward on the shelf,and are dissipated rapidly. When the Vaisala frequency decreases vertically, waves may be mostly limited to thecontinental slope region. in deep sea region, motions may have either boam-like structure or modal structure,depending on the stratification strerigth and structure, whereas a modal structure may always exist onthe shelf. Waves show strong bottom intensification on the slope when strong stratification exists on thebottom. The barotropic tidal advection may affed the temporal character of internal tides at thecontinental slope, shelf break and shelf regions. but may have little influence on the energy density and energy flux of internal tides. ln the case of strong stratification, waverforms
基金National Enucation Committee Foundation Prgrams 9142305 and 9342305National Natural Science Foundation Program 49376257National Special Research Program 85-927-05-03
文摘By using a coordinate transformation, an exact solution of internal tides with sub-inertial frequency isobtained when the bottom slope is linear and the Vaisala frequency is constant. Accordingly thedispersion relations of free waves are presented. This solution is suitable for general coastal low-frequencybaroclinic waves with zero alongshore wavenumber.
文摘By using part of CTD data collected at 2°S, 155° E during the fall cruise of TOGA project in 1992, themultifractal characters of temperature finestructures are investigated. The absolute temperature gradients are supposedto be multifractal and their moments are computed by conventional box-counting method. It is found that these moments have power dependence on the box size. This power dependence has two different scaling regimes, called Sregime and I-regime resistively, with different scaling exponents. This is consistent with the combined effects of internal waves and boxing. Accordingly, the generalized fractal dimensions (Renyi dimension) of temperature gradientsare derived. A nonlinear curve of the scaling exponents suggest a possible multifractal approach of the temperatureshear. In fact, both regimes can be approximated by Besicovitch- Cantor model, respectively, by suitably chosenmoduel parameters. A phenomenological model is developed on the basis of this two-regime mechanism. The model iscompared with field data and good agreement is achieved.