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| Titel |
Computing rare transitions between zonal mid-latitude jets |
| VerfasserIn |
Eric Simonnet, Freddy Bouchet |
| Konferenz |
EGU General Assembly 2016
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250127526
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| Publikation (Nr.) |
 EGU/EGU2016-7415.pdf |
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| Zusammenfassung |
| Zonal jets are known to naturally emerge from beta-plane turbulence due to the arrest of
inverse energy cascade by Rossby waves.Transitions between jets of different wavenumber
are indeed observed in particular regimes showing a striking example of bimodality in the
context of 2-D turbulence. As the Rayleigh dissipation and stochastic forcing are decreased
these transitions become more and more rare.
The aim of this talk is to show that it is possible to compute large ensembles of reactive
trajectories connecting the different metastable states even at very low probability
regimes when direct numerical simulations are not possible. We use an adaptive
version of multilevel splitting algorithms on a barotropic quasi geostrophic model of
mid-latitude atmosphere. We are able to obtain a detailed statistical description of the
high-dimensional phase space as well as the typical transitions. A large-deviation result is
also obtained. |
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