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| Titel |
Jets and storm tracks in γ-plane models |
| VerfasserIn |
Maarten Ambaum, Ben Harvey |
| Konferenz |
EGU General Assembly 2013
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 15 (2013) |
| Datensatznummer |
250076579
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| Zusammenfassung |
| We will present new results from linear calculations and non-linear simulations of a
two-layer baroclinic γ–plane model. The model consists of two interacting levels with
dynamical temperature anomalies (as in the Eady model), but by its nature provides a
consistent description of the continuous 3-dimensional velocity field inside the
domain. Our set-up has realistic jet-profiles, yet has a very low-dimensional parameter
space.
The model is shown to exhibit realistic linear baroclinic instability properties. In addition,
it is shown that the introduction of a γ–plane term induces a jet and a storm-track that is
highly non-linear: it exhibits a realistic spiral jet structure and jet-exit region, as is the
case for the observed N. Hemisphere jet on Earth. This seems to imply that the
variability of the N. Atlantic jet stream is not the result of complex topographic and
orographic boundary conditions in the N. Hemisphere, as recent simulations appear to
suggest, but rather the result of the spherical geometry of the Earth, setting the right
conditions for relevant non-linear interactions between Rossby waves and the jet. |
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