Biological and Environmental Research - Earth and Environmental System Sciences
Earth and Environmental System Modeling

A Framework to Evaluate IMEX Schemes for Atmospheric Models

TitleA Framework to Evaluate IMEX Schemes for Atmospheric Models
Publication TypeJournal Article
Year of Publication2020
JournalGeoscientific Model Development
Volume13
Number12
Pages6467-6480
Abstract / Summary

We present a new evaluation framework for implicit and explicit (IMEX) Runge–Kutta time-stepping schemes. The new framework uses a linearized non-hydrostatic system of normal modes. We utilize the framework to investigate the stability of IMEX methods and their dispersion and dissipation of gravity, Rossby, and acoustic waves. We test the new framework on a variety of IMEX schemes and use it to develop and analyze a set of second-order low-storage IMEX Runge–Kutta methods with a high Courant–Friedrichs–Lewy (CFL) number. We show that the new framework is more selective than the 2-D acoustic system previously used in the literature. Schemes that are stable for the 2-D acoustic system are not stable for the system of normal modes.

URLhttp://dx.doi.org/10.5194/gmd-13-6467-2020
DOI10.5194/gmd-13-6467-2020
Journal: Geoscientific Model Development
Year of Publication: 2020
Volume: 13
Number: 12
Pages: 6467-6480
Publication Date: 12/2020

We present a new evaluation framework for implicit and explicit (IMEX) Runge–Kutta time-stepping schemes. The new framework uses a linearized non-hydrostatic system of normal modes. We utilize the framework to investigate the stability of IMEX methods and their dispersion and dissipation of gravity, Rossby, and acoustic waves. We test the new framework on a variety of IMEX schemes and use it to develop and analyze a set of second-order low-storage IMEX Runge–Kutta methods with a high Courant–Friedrichs–Lewy (CFL) number. We show that the new framework is more selective than the 2-D acoustic system previously used in the literature. Schemes that are stable for the 2-D acoustic system are not stable for the system of normal modes.

DOI: 10.5194/gmd-13-6467-2020
Citation:
Guba, O, MA Taylor, AM Bradley, PA Bosler, and A Steyer.  2020.  "A Framework to Evaluate IMEX Schemes for Atmospheric Models."  Geoscientific Model Development 13(12): 6467-6480.  https://doi.org/10.5194/gmd-13-6467-2020.