Journal article icon

Journal article

Breeding and predictability in the baroclinic rotating annulus using a perfect model

Abstract:
We present results from a computational study of predictability in fully-developed baroclinically unstable laboratory flows. This behaviour is studied in the Met Office/Oxford Rotating Annulus Laboratory Simulation - a model of the classic rotating annulus laboratory experiment with differentially heated cylindrical sidewalls, which is firmly established as an insightful laboratory analogue for certain kinds of atmospheric dynamical behaviour. This work is the first study of "predictability of the first kind" in the annulus experiment. We devise an ensemble prediction scheme using the breeding method to study the predictability of the annulus in the perfect model scenario. This scenario allows one simulation to be defined as the true state, against which all forecasts are measured. We present results from forecasts over a range of quasi-periodic and chaotic annulus flow regimes. A number of statistical and meteorological techniques are used to compare the predictability of these flows: bred vector growth rate and dimension, error variance, "spaghetti plots", probability forecasts, Brier score, and the Kolmogorov-Smirnov test. These techniques gauge both the predictability of the flow and the performance of the ensemble relative to a forecast using a climatological distribution. It is found that in the perfect model scenario, the two quasi-periodic regimes examined may be indefinitely predictable. The two chaotic regimes (structural vacillation and period doubled amplitude vacillation) show a loss of predictability on a timescale of hundreds to thousands of seconds (65-280 annulus rotation periods, or 1-3 Lyapunov times).
Publication status:
Published
Peer review status:
Peer reviewed

Actions


Access Document


Authors


More by this author
Institution:
University of Oxford
Division:
MPLS
Department:
Physics
Sub department:
Atmos Ocean & Planet Physics
Research group:
Geophysical and Planetary Fluid Dynamics group
Oxford college:
Linacre College
Role:
Author
More by this author
Institution:
University of Oxford
Division:
MPLS
Department:
Physics
Sub department:
Atmos Ocean & Planet Physics
Research group:
Geophysical and Planetary Fluid Dynamics group
Oxford college:
Trinity College
Role:
Author

Contributors


More from this funder
Funding agency for:
Young, R
Grant:
NER/S/A/2005/13667


Publisher:
Copernicus Publications
Journal:
Nonlinear Processes in Geophysics More from this journal
Volume:
15
Pages:
469-487
Publication date:
2008-06-01
Edition:
Publisher's version
EISSN:
1607-7946
ISSN:
1023-5809


Language:
English
Keywords:
Subjects:
UUID:
uuid:480a3057-029c-4771-a123-5f5e1678c90f
Local pid:
ora:2756
Deposit date:
2009-04-30

Terms of use



Views and Downloads






If you are the owner of this record, you can report an update to it here: Report update to this record

TO TOP