hide
Free keywords:
-
Abstract:
Lagrangian analysis using particle tracking system plays major roles in recent ocean modeling studies. The targets of Lagrangian analysis include water properties, dissolved or particulate elements, marine debris such as microplastics and oil droplets, suspended sediment matters, passively transported eggs, plankton, and larvae, and even actively migrating fishes. The Lagrangian particle tracking method has several advantages over Eulerian tracers such as the ability to record the history of each individual particle and the high accuracy of advection without contamination from numerical diffusion and dissipation. However, the reliability of Lagrangian analysis highly depends on the spatial resolution of the velocity field in which the particle trajectories are integrated. In the present study, we developed a high-resolution modeling system with 1/180deg resolution covering the entire Japanese archipelago and neighboring shelf regions with deploying multi-billion passive particles to trace the small-scale trajectory of water mass and dissipation/dilution mechanisms. The results enable us to assess the connectivity between remote bays and regions, which is essential for fishery/marine resource studies. The time progress of packet envelopes of particles initially deployed within narrow regions quantitatively exhibits anisotropic diffusivity reflecting submesoscale shear and eddy activities.
