A Semi-Implicit Semi-Lagrangian Finite-Element Shallow-Water Ocean Model
نویسندگان
چکیده
The nite-element, semi-implicit, and semi-Lagrangian methods are combined together to solve the shallow-water equations using unstructured triangular meshes. Triangular nite elements are attractive for ocean modeling because of their exibility for representing irregular boundaries and for local mesh re nement. A \kriging" interpolator is used for the semi-Lagrangian advection, leading to an accurate representation of the slow Rossby modes. The terms that govern fast gravitational oscillations are discretized using the semi-implicit scheme, thereby circumventing a severe timestep restriction. A loworder velocity / surface-elevation nite-element basis-function pair is used for the spatial discretization. Results of test problems to simulate slowly-propagating Rossby modes illustrate the promise of the proposed approach for ocean modeling.
منابع مشابه
Finite Elements for Shallow-Water Equation Ocean Models
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