Campus Units
Geological and Atmospheric Sciences
Document Type
Article
Publication Version
Published Version
Publication Date
12-2011
Journal or Book Title
Acta Geophysica
Volume
59
Issue
6
First Page
1135
Last Page
1157
DOI
10.2478/s11600-011-0050-0
Abstract
EULAG is a computational model for simulating flows across a wide range of scales and physical scenarios. A standard option employs an anelastic approximation to capture nonhydrostatic effects and simultaneously filter sound waves from the solution. In this study, we examine a localized gravity wave packet generated by instabilities in Held-Suarez climates. Although still simplified versus the Earth’s atmosphere, a rich set of planetary wave instabilities and ensuing radiated gravity waves can arise. Wave packets are observed that have lifetimes ≤ 2 days, are negligibly impacted by Coriolis force, and do not show the rotational effects of differential jet advection typical of inertia-gravity waves. Linear modal analysis shows that wavelength, period, and phase speed fit the dispersion equation to within a mean difference of ∼ 4%, suggesting an excellent fit. However, the group velocities match poorly even though a propagation of uncertainty analysis indicates that they should be predicted as well as the phase velocities. Theoretical arguments suggest the discrepancy is due to nonlinearity — a strong southerly flow leads to a critical surface forming to the southwest of the wave packet that prevents the expected propagation.
Rights
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License. (CC BY-NC-ND 3.0)
Copyright Owner
Institute for Geophysics, Polish Academy of Sciences
Copyright Date
2012
Language
en
File Format
application/pdf
Recommended Citation
Prusa, Joseph and Gutowski, William, "Multi-scale waves in sound-proof global simulations with EULAG" (2011). Geological and Atmospheric Sciences Publications. 127.
https://lib.dr.iastate.edu/ge_at_pubs/127
Comments
This article is from Acta Geophysica. Volume 59, Issue 6, Pages 1135–1157, ISSN (Online) 1895-7455, ISSN (Print) 1895-6572, DOI: 10.2478/s11600-011-0050-0, October 2011