Title: On the numerical asymmetry in calculating Coriolis terms through the splitting method in a mesoscale model
Authors: Pinhas Alpert, Hannu Savijarvi
Addresses: Raymond and Beverly Sackler Faculty of Exact Sciences, Department of Geophysics and Planetary Sciences, Tel Aviv University, Tel Aviv 69978, Israel. ' Division of Atmospheric Sciences, Department of Physical Sciences, FIN-00014 University of Helsinki, P.O. Box 64, Helsinki, Finland
Abstract: The asymmetry in calculating the Coriolis terms by Marchuk|s splitting method is discussed. It was found that although some asymmetry is required for linear stability, this asymmetry should be kept to a minimum. Otherwise, for instance, if the diffusion terms are calculated in between the Coriolis terms in the u and v equations of motion, one gets cross-isobaric low-level winds, which are different depending on the geostrophic wind direction. This is the first study to show that the required asymmetry in the splitting can cause a considerable error in the boundary-layer winds of atmospheric models if not handled in a specific way.
Keywords: splitting method; mesoscale models; Ekman spiral; numerical asymmetry; Coriolis terms; geostrophic wind direction; environmental modelling.
International Journal of Environment and Pollution, 2008 Vol.32 No.2, pp.139 - 148
Published online: 13 Feb 2008 *Full-text access for editors Access for subscribers Purchase this article Comment on this article