The particle trajectory on a weakly nonlinear progressive surface wave obliquely interacting with a uniform current is studied by using an Euler-Lagrange transformation.The third-order asymptotic solution is a periodi...The particle trajectory on a weakly nonlinear progressive surface wave obliquely interacting with a uniform current is studied by using an Euler-Lagrange transformation.The third-order asymptotic solution is a periodic bounded function of Lagrangian labels and time,which imply that the entire solution is uniformly-valid.The explicit parametric solution highlights the trajectory of a water particle and mass transport associated with a particle displacement can now be obtained directly in Lagrangian form.The angular frequency and Lagrangian mean level of the particle motion in Lagrangian form differ from those of the Eulerian.The variations in the water particle orbits resulting from the oblique interaction with a steady uniform current of different magnitudes are also investigated.展开更多
Based on the statistics of all surface drifting buoys of 1978-2011 and Lagrangian tracers simulated from high quality ocean reanalysis currents,the impact times and strength of Fukushima nuclear pollution to the east ...Based on the statistics of all surface drifting buoys of 1978-2011 and Lagrangian tracers simulated from high quality ocean reanalysis currents,the impact times and strength of Fukushima nuclear pollution to the east coast of China and the west coast of America have been estimated.Under the circumstances of the radioactive pollutants drifting in the ocean surface,preliminary research results show that while the tracers took about 4 years to reach the west coast of USA,there are two types of tracers to carry out Fukushima nuclear pollutants to reach the east coast of China,corresponding to 1.5-year recirculation gyre transport and 3.5-year subtropical circulation transport.The distributions of the impact strength at these time scales are given according to the variation of relative number concentration with time combined with the decaying rate of radioactive matter.For example,starting from 1% at 1.5-year,of the initial level at the originating area of Fukushima nuclear pollution,the impact strength of Cesium-137 in the South China Sea continuously increases up to 3% by 4 years,while the impact strength of Cesium-137 in the west coast of America is as high as 4% due to the role of strong Kuroshio-extension currents as a major transport mechanism of nuclear pollutants for that area.展开更多
基金National Science Council in Taiwan 97-2221-E-230-023
文摘The particle trajectory on a weakly nonlinear progressive surface wave obliquely interacting with a uniform current is studied by using an Euler-Lagrange transformation.The third-order asymptotic solution is a periodic bounded function of Lagrangian labels and time,which imply that the entire solution is uniformly-valid.The explicit parametric solution highlights the trajectory of a water particle and mass transport associated with a particle displacement can now be obtained directly in Lagrangian form.The angular frequency and Lagrangian mean level of the particle motion in Lagrangian form differ from those of the Eulerian.The variations in the water particle orbits resulting from the oblique interaction with a steady uniform current of different magnitudes are also investigated.
基金supported by National Natural Science Foundation of China(Grant Nos. 41030854,40906015,40906016,41106005,and 41176003)
文摘Based on the statistics of all surface drifting buoys of 1978-2011 and Lagrangian tracers simulated from high quality ocean reanalysis currents,the impact times and strength of Fukushima nuclear pollution to the east coast of China and the west coast of America have been estimated.Under the circumstances of the radioactive pollutants drifting in the ocean surface,preliminary research results show that while the tracers took about 4 years to reach the west coast of USA,there are two types of tracers to carry out Fukushima nuclear pollutants to reach the east coast of China,corresponding to 1.5-year recirculation gyre transport and 3.5-year subtropical circulation transport.The distributions of the impact strength at these time scales are given according to the variation of relative number concentration with time combined with the decaying rate of radioactive matter.For example,starting from 1% at 1.5-year,of the initial level at the originating area of Fukushima nuclear pollution,the impact strength of Cesium-137 in the South China Sea continuously increases up to 3% by 4 years,while the impact strength of Cesium-137 in the west coast of America is as high as 4% due to the role of strong Kuroshio-extension currents as a major transport mechanism of nuclear pollutants for that area.
