Differences in the sub-seasonal predictability of extreme stratospheric events
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Published:2022-07-15
Issue:3
Volume:3
Page:755-776
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ISSN:2698-4016
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Container-title:Weather and Climate Dynamics
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language:en
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Short-container-title:Weather Clim. Dynam.
Author:
Wu Rachel Wai-YingORCID, Wu ZhengORCID, Domeisen Daniela I.V.ORCID
Abstract
Abstract. Extreme stratospheric events such as sudden stratospheric warming (SSW) and strong vortex events can have downward impacts on surface weather that can last for several weeks to months. Hence, successful predictions of these stratospheric events can be beneficial for extended-range weather prediction. However, the predictability of extreme stratospheric events is most often limited to around 2 weeks or less. The predictability strongly differs within events of the same type and also between event types. The reasons for the observed differences in the predictability, however, are not resolved. We extend the analysis of the predictability of stratospheric extreme events to include wind deceleration and acceleration events, with SSW and strong vortex events as subsets, to conduct a systematic comparison of sub-seasonal predictability between events in the European Centre for Medium-Range Weather Forecasts (ECMWF) prediction system. Events of stronger magnitude are found to be less predictable than weaker events for both wind deceleration and acceleration events, with both types of events showing a close to linear dependence of predictability on event magnitude. There are, however, deviations from this linear behaviour for very strong magnitude events. The difficulties of the prediction system in predicting extremely strong anomalies can be traced to a poor predictability of extreme wave activity fluxes in the lower stratosphere, which impacts the prediction of deceleration events and, interestingly, also acceleration events. Our study suggests that improvements in the understanding of the wave amplification that is associated with extremely strong wave activity fluxes and accurately representing these processes in the model are expected to enhance the predictability of stratospheric extreme events and, by extension, their impacts on surface weather and climate.
Funder
Eidgenössische Technische Hochschule Zürich Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung
Publisher
Copernicus GmbH
Reference56 articles.
1. Albers, J. R. and Birner, T.: Vortex preconditioning due to planetary and
gravity waves prior to sudden stratospheric warmings, J. Atmos. Sci., 71, 4028–4054, https://doi.org/10.1175/JAS-D-14-0026.1, 2014. a, b, c, d 2. Ayarzagüena, B., Langematz, U., and Serrano, E.:
Tropospheric forcing of the stratosphere: A comparative study of the two
different major stratospheric warmings in 2009 and 2010, J. Geophys. Res.-Atmos., 116, D18114, https://doi.org/10.1029/2010JD015023, 2011. a 3. Baldwin, M. P. and Dunkerton, T. J.: Stratospheric Harbingers of Anomalous
Weather Regimes, Science, 294, 581–584, https://doi.org/10.1126/science.1063315, 2001. a, b 4. Baldwin, M. P., Ayarzagüena, B., Birner, T.,
Butchart, N., Butler, A. H., Charlton-Perez, A. J., Domeisen, D. I. V.,
Garfinkel, C. I., Garny, H., Gerber, E. P., Hegglin, M. I., Langematz, U.,
and Pedatella, N. M.: Sudden Stratospheric Warmings, Rev. Geophys., 59,
e2020RG000708, https://doi.org/10.1029/2020RG000708, 2021. a 5. Birner, T. and Albers, J. R.: Sudden Stratospheric Warmings and Anomalous
Upward Wave Activity Flux, SOLA, 13A, 8–12, https://doi.org/10.2151/sola.13A-002,
2017. a, b, c, d
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