The role of the stratosphere in subseasonal to seasonal prediction part I: predictability of the stratosphere

Domeisen, D. I. V., Butler, A. H., Charlton-Perez, A. J. ORCID: https://orcid.org/0000-0001-8179-6220, Ayarzagüena, B., Baldwin, M. P., Dunn‐Sigouin, E., Furtado, J. C., Garfinkel, C. I., Hitchcock, P., Karpechko, A. Y., Kim, H., Knight, J., Lang, A. L., Lim, E.‐P., Marshall, A., Roff, G., Schwartz, C., Simpson, I. R., Son, S.‐W. and Taguchi, M. (2020) The role of the stratosphere in subseasonal to seasonal prediction part I: predictability of the stratosphere. Journal of Geophysical Research: Atmospheres, 125 (2). e2019JD030920. ISSN 2169-8996 doi: 10.1029/2019jd030920

Abstract/Summary

The stratosphere has been identified as an important source of predictability for a range of processes on subseasonal to seasonal (S2S) timescales. Knowledge about S2S predictability within the stratosphere is however still limited. This study evaluates to what extent predictability in the extratropical stratosphere exists in hindcasts of operational prediction systems in the S2S database. The stratosphere is found to exhibit extended predictability as compared to the troposphere. Prediction systems with higher stratospheric skill tend to also exhibit higher skill in the troposphere. The analysis also includes an assessment of the predictability for stratospheric events, including early and mid‐winter sudden stratospheric warming (SSW) events, strong vortex events, and extreme heat flux events for the Northern Hemisphere, and final warming events for both hemispheres. Strong vortex events and final warming events exhibit higher levels of predictability as compared to SSW events. In general, skill is limited to the deterministic range of one to two weeks. High‐top prediction systems overall exhibit higher stratospheric prediction skill as compared to their low‐top counterparts, pointing to the important role of stratospheric representation in S2S prediction models.

Item Type	Article
URI	https://reading-clone.eprints-hosting.org/id/eprint/87643
Identification Number/DOI	10.1029/2019jd030920
Refereed	Yes
Divisions	Science > School of Mathematical, Physical and Computational Sciences > Department of Meteorology
Publisher	American Geophysical Union
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