Stratospheric modulation of Arctic Oscillation extremes as represented by extended-range ensemble forecasts

Spaeth, Jonas; Birner, Thomas

doi:https://doi.org/10.5194/wcd-3-883-2022

Articles | Volume 3, issue 3

https://doi.org/10.5194/wcd-3-883-2022

© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

https://doi.org/10.5194/wcd-3-883-2022

© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 3, issue 3

Research article

|

05 Aug 2022

Research article |

| 05 Aug 2022

Stratospheric modulation of Arctic Oscillation extremes as represented by extended-range ensemble forecasts

Jonas Spaeth and Thomas Birner

Supplement

https://doi.org/10.5194/wcd-3-883-2022-supplement

Data sets

The subseasonal to seasonal (S2S) prediction project database (https://apps.ecmwf.int/datasets/data/s2s) F. Vitart, C. Ardilouze, A. Bonet, A. Brookshaw, M. Chen, C. Codorean, M. Déqué, L. Ferranti, E. Fucile, M., Fuentes, H. H. Hendon, J. Hodgson, H. S. Kang, A. Kumar, H. Lin, G. Liu, X. Liu, P. Malguzzi, I. Mallas, M. Manoussakis, D. Mastrangelo, C. MacLachlan, P. McLean, A. Minami, R. Mladek, T. Nakazawa, S. Najm, Y. Nie, M. Rixen, A. W. Robertson, P. Ruti, C. Sun, Y. Takaya, M. Tolstykh, F. Venuti, D. Waliser, S. Woolnough, T. Wu, D. J. Won, H. Xiao, R. Zaripov, and L. Zhang https://doi.org/10.1175/BAMS-D-16-0017.1

ERA5 hourly data on pressure levels from 1959 to present H. Hersbach, B. Bell, P. Berrisford, G. Biavati, A. Horányi, J. Muñoz Sabater, J. Nicolas, C. Peubey, R. Radu, I. Rozum, D. Schepers, A. Simmons, C. Soci, D. Dee, and J.-N. Thépaut https://doi.org/10.24381/cds.bd0915c6

Short summary

Past research has demonstrated robust stratosphere–troposphere dynamical coupling following stratospheric circulation extremes. Here, we use a large set of extended-range ensemble forecasts to robustly quantify the increased risk for tropospheric circulation extremes following stratospheric extreme events. In particular, we provide estimates of the fraction of tropospheric extremes that may be attributable to preceding stratospheric extremes.