The suite of Taylor–Galerkin class schemes for ice transport on sphere implemented by the INMOST package

Abstract Realizations of the numerical solution of the scalar transport equation on the sphere, written in divergent form, are presented. Various temporal discretizations are considered: the one-step Taylor–Galerkin method (TG2), the two-step Taylor–Galerkin method of the second (TTG2), third (TTG3)...

Full description

Bibliographic Details
Published in:Russian Journal of Numerical Analysis and Mathematical Modelling
Main Authors: Petrov, Sergey S., Iakovlev, Nikolay G.
Format: Article in Journal/Newspaper
Language:English
Published: Walter de Gruyter GmbH 2021
Subjects:
Online Access:http://dx.doi.org/10.1515/rnam-2021-0019
https://www.degruyter.com/document/doi/10.1515/rnam-2021-0019/xml
https://www.degruyter.com/document/doi/10.1515/rnam-2021-0019/pdf
Description
Summary:Abstract Realizations of the numerical solution of the scalar transport equation on the sphere, written in divergent form, are presented. Various temporal discretizations are considered: the one-step Taylor–Galerkin method (TG2), the two-step Taylor–Galerkin method of the second (TTG2), third (TTG3), and fourth (TTG4) orders. The standard Finite-Element Galerkin method with linear basis functions on a triangle is applied as spatial discretization. The flux correction technique (FCT) is implemented. Test runs are carried out with different initial profiles: a function from C ∞ (Gaussian profile) and a discontinuous function (slotted cylinder). The profiles are advected by reversible, nondivergent velocity fields, therefore the initial distribution coincides with the final one. The case of a divergent velocity field is also considered to test the conservation and positivity properties of the schemes. It is demonstrated that TG2, TTG3, and TTG4 schemes with FCT applied give the best result for small Courant numbers, and TTG2, TTG4 are preferable in case of large Courant number. However, TTG2+FCT scheme has the worst stability. The use of FCT increases the integral errors, but ensures that the solution is positive with high accuracy. The implemented schemes are included in the dynamic core of a new sea ice model developed using the INMOST package. The acceleration of the parallel program and solution convergence with spatial resolution are demonstrated.