Test of a cubic spline interface for physical processes with a 1-D third-order spectral element model
File(s)
Published version
Author(s)
Steppeler, J
Li, J
Fang, F
Zhu, J
Type
Journal Article
Abstract
A common way to introduce physical processes into numerical models of the atmosphere is to call the parameterization at every grid point. This can lead to considerable errors. A simple 1-D example is proposed to illustrate that when a physical process occurs at one grid point only, a considerable sampling error may occur, with the result that only a fraction of the true impact of this process is seen. The interface to the physical parameterization in numerical weather prediction model using a third-order 1-D spectral element method (SEM3) model is investigated by homogeneous advection. In SEM3, the grid points, called principal nodes, are at boundaries of computational intervals and two more collocation points in the interior of each cell. This article argues that it is sufficient to do the physical parameterization for principal nodes only that creating the interior grid-point values of physics schemes by linear interpolation. This is called the spline interface method. A simple condensation model of water is taken as an example. Compared to the standard paramaterization, which computes the physical processes at every grid point, the spline interface method is more accurate and has a potential to save computer time. It turns out that the standard method creates a noisy wave which can easily be filtered by hyperviscosity. In the spline interface to the condensation physics, the condensation is done at every third grid point only. Third-order spline methods are used to represent the condensation at other points. The method using a smaller grid to compute condensation represented the condensation process more accurately and produced less of the computational noise. This version could be run without hyperviscosity, as no significant computational noise mode was generated by condensation. By doing physical processes only at every third grid point computer time may be saved.
Date Issued
2019-04-01
Date Acceptance
2019-04-01
Citation
Tellus Series A: Dynamic Meteorology and Oceanography, 2019, 71 (1), pp.1-6
ISSN
0280-6495
Publisher
Taylor & Francis
Start Page
1
End Page
6
Journal / Book Title
Tellus Series A: Dynamic Meteorology and Oceanography
Volume
71
Issue
1
Copyright Statement
© 2019 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Sponsor
Engineering & Physical Science Research Council (E
Identifier
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000463016200001&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
Grant Number
RG80519
Subjects
Science & Technology
Physical Sciences
Meteorology & Atmospheric Sciences
Oceanography
physical process interface
L-Galerkin method
spectral element method
sparse grid
physical parameterization
COORDINATE
MOUNTAIN
GRIDS
Publication Status
Published
Date Publish Online
2019-04-01