Rotating shallow water flow under location uncertainty with a structure‐preserving discretization
OA Location
Author(s)
Brecht, Rüdiger
Li, Long
Bauer, Werner
Mémin, Etienne
Type
Journal Article
Abstract
We introduce a physically relevant stochastic representation of the rotating shallow water equations. The derivation relies mainly on a stochastic transport principle and on a decomposition of the fluid flow into a large-scale component and a noise term that models the unresolved flow components. As for the classical (deterministic) system, this scheme, referred to as modelling under location uncertainty (LU), conserves the global energy of any realization and provides the possibility to generate an ensemble of physically relevant random simulations with a good trade-off between the model error representation and the ensemble’s spread. To maintain numerically the energy conservation feature, we combine an energy (in space) preserving discretization of the underlying deterministic model with approximations of the stochastic terms that are based on standard finite volume/difference operators. The LU derivation, built from the very same conservation principles as the usual geophysical models, together with the numerical scheme proposed can be directly used in existing dynamical cores of global numerical weather prediction models. The capabilities of the proposed framework is demonstrated for an inviscid test case on the f-plane and for a barotropically unstable jet on the sphere.
Date Issued
2021-12
Date Acceptance
2021-10-11
Citation
Journal of Advances in Modeling Earth Systems, 2021, 13 (12), pp.1-28
ISSN
1942-2466
Publisher
American Geophysical Union (AGU)
Start Page
1
End Page
28
Journal / Book Title
Journal of Advances in Modeling Earth Systems
Volume
13
Issue
12
Copyright Statement
© 2021 The Authors. Journal of Advances in Modeling Earth Systems published by Wiley Periodicals LLC on behalf of American Geophysical Union.
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
License URL
Sponsor
Natural Environment Research Council (NERC)
Identifier
https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2021MS002492
Grant Number
NE/R008795/1
Subjects
physics.flu-dyn
physics.flu-dyn
cs.NA
math.NA
0401 Atmospheric Sciences
Publication Status
Published
Date Publish Online
2021-10-21