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arXiv · 2011.03389

Multi-modal excitation to model the Quasi-Biennial Oscillation

Pierre Léard·Daniel Lecoanet·Michael Le Bars
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Abstract

The Quasi-Biennial Oscillation (QBO) of stratospheric winds is the most striking example of mean-flow generation and reversal by the non-linear interactions of internal waves. Previous studies have used an idealized monochromatic forcing to investigate the QBO. Here we instead force a more realistic continuous wave spectrum. Unexpectedly, spreading the wave energy across a wide frequency range leads to more regular oscillations. We also find that different forcing spectra can yield the same QBO. Multi-modal wave forcing is thus essential for understanding wave/mean-flow interactions in nature.

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BibTeXRIS

Pierre Léard, Daniel Lecoanet, Michael Le Bars. 2020-11-06. Multi-modal excitation to model the Quasi-Biennial Oscillation. https://doi.org/10.1103/physrevlett.125.234501

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