edu.ucar.opensky::articles:23218 UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact 2025-12-25T15:17:18.127564 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) https://n2t.org/ark:/85065/d7b56nzn The role of the stratosphere in subseasonal to seasonal prediction: 2. Predictability arising from stratosphere-troposphere coupling 2020-01-27T00:00:00Z publication https://n2t.org/ark:/85065/d7b56nzn https://doi.org/10.1029/2019JD030923 Domeisen, D. I. V. author Butler, A. H. author Charlton-Perez, A. J. author Ayarzagüena, B. author Baldwin, M. P. author Dunn-Sigouin, E. author Furtado, J. C. author Garfinkel, C. I. author HITCHCOCK, P. author Karpechko, A. Y. author Kim, H. author Knight, J. author Lang, A. L. author Lim, E. author Marshall, A. author Roff, G. author Schwartz, C. author Simpson, Isla R. author Son, S. author Taguchi, M. author UCAR/NCAR - Library publisher The stratosphere can have a significant impact on winter surface weather on subseasonal to seasonal (S2S) timescales. This study evaluates the ability of current operational S2S prediction systems to capture two important links between the stratosphere and troposphere: (1) changes in probabilistic prediction skill in the extratropical stratosphere by precursors in the tropics and the extratropical troposphere and (2) changes in surface predictability in the extratropics after stratospheric weak and strong vortex events. Probabilistic skill exists for stratospheric events when including extratropical tropospheric precursors over the North Pacific and Eurasia, though only a limited set of models captures the Eurasian precursors. Tropical teleconnections such as the Madden-Julian Oscillation, the Quasi-Biennial Oscillation, and El Nino-Southern Oscillation increase the probabilistic skill of the polar vortex strength, though these are only captured by a limited set of models. At the surface, predictability is increased over the United States, Russia, and the Middle East for weak vortex events, but not for Europe, and the change in predictability is smaller for strong vortex events for all prediction systems. Prediction systems with poorly resolved stratospheric processes represent this skill to a lesser degree. Altogether, the analyses indicate that correctly simulating stratospheric variability and stratosphere-troposphere dynamical coupling are critical elements for skillful S2S wintertime predictions. UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact PDF Text theme Resource Type 2016-01-01T00:00:00Z publication Copyright 2020 American Geophysical Union None eng geoscientificInformation