Articles | Volume 26, issue 11
https://doi.org/10.5194/nhess-26-5733-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/nhess-26-5733-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
11 Nov 2026
Research article |
| 11 Nov 2026
| 11 Nov 2026
Quantifying the attributable impact of the February 2018 sudden stratospheric warming on mortality in the Nordics and United Kingdom
Meteorological Institute Munich, Ludwig Maximilian University of Munich, Munich, Germany
Liliana Vázquez Fernández
Division for Climate and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway
Department of Biostatistics, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
William J. M. Seviour
CORRESPONDING AUTHOR
Department of Mathematics and Statistics and Global Systems Institute, University of Exeter, Exeter, UK
Thomas Birner
Meteorological Institute Munich, Ludwig Maximilian University of Munich, Munich, Germany
Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Physik der Atmosphäre, Oberpfaffenhofen, Germany
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Frederik Harzer, Hella Garny, Felix Ploeger, Harald Bönisch, Peter Hoor, and Thomas Birner
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We study the statistical relation between year-by-year fluctuations in winter-mean ozone and the strength of the stratospheric polar vortex. In the latitude–pressure plane, regression analysis shows that anomalously weak polar vortex years are associated with three pronounced local ozone maxima over the polar cap relative to the winter climatology. These response maxima primarily reflect the non-trivial combination of different ozone transport processes with varying relative contributions.
Flossie Brown, Lauren Marshall, Peter H. Haynes, Rolando R. Garcia, Thomas Birner, and Anja Schmidt
Atmos. Chem. Phys., 23, 5335–5353, https://doi.org/10.5194/acp-23-5335-2023, https://doi.org/10.5194/acp-23-5335-2023, 2023
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Large-magnitude volcanic eruptions have the potential to alter large-scale circulation patterns, such as the quasi-biennial oscillation (QBO). The QBO is an oscillation of the tropical stratospheric zonal winds between easterly and westerly directions. Using a climate model, we show that large-magnitude eruptions can delay the progression of the QBO, with a much longer delay when the shear is easterly than when it is westerly. Such delays may affect weather and transport of atmospheric gases.
Felix Jäger, Philip Rupp, and Thomas Birner
Weather Clim. Dynam., 4, 49–60, https://doi.org/10.5194/wcd-4-49-2023, https://doi.org/10.5194/wcd-4-49-2023, 2023
Short summary
Short summary
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Jonas Spaeth and Thomas Birner
Weather Clim. Dynam., 3, 883–903, https://doi.org/10.5194/wcd-3-883-2022, https://doi.org/10.5194/wcd-3-883-2022, 2022
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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.
Corwin J. Wright, Richard J. Hall, Timothy P. Banyard, Neil P. Hindley, Isabell Krisch, Daniel M. Mitchell, and William J. M. Seviour
Weather Clim. Dynam., 2, 1283–1301, https://doi.org/10.5194/wcd-2-1283-2021, https://doi.org/10.5194/wcd-2-1283-2021, 2021
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Major sudden stratospheric warmings (SSWs) are some of the most dramatic events in the atmosphere and are believed to help cause extreme winter weather events such as the 2018 Beast from the East in Europe and North America. Here, we use unique data from the European Space Agency's new Aeolus satellite to make the first-ever measurements at a global scale of wind changes due to an SSW in the lower part of the atmosphere to help us understand how SSWs affect the atmosphere and surface weather.
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Short summary
We study mortality impacts of sudden stratospheric warmings (SSWs) via counterfactual ensemble simulations. SSWs robustly increase the likelihood of cold spells in Northern Europe, but the socio-economic effects remain poorly quantified. Using re-forecasts of the 2018 SSW and mortality records, we attribute hundreds of expected deaths in the UK and Nordics to this event. The strongest impacts emerge from combined post-SSW cold anomalies and heightened mortality sensitivity to these anomalies.
We study mortality impacts of sudden stratospheric warmings (SSWs) via counterfactual ensemble...
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