Preprints
https://doi.org/10.5194/egusphere-2024-1652
https://doi.org/10.5194/egusphere-2024-1652
05 Jun 2024
 | 05 Jun 2024
Status: this preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).

Tropospheric Links to Uncertainty in Stratospheric Subseasonal Predictions

Rachel W.-Y. Wu, Gabriel Chiodo, Inna Polichtchouk, and Daniela I. V. Domeisen

Abstract. Variability in the stratosphere, especially extreme events such as Sudden Stratospheric Warmings (SSWs), can impact surface weather. Understanding stratospheric prediction uncertainty is therefore crucial for skillful surface weather forecasts on weekly to monthly timescales. Using ECMWF subseasonal hindcasts, this study finds that stratospheric uncertainty is most strongly linked to tropospheric uncertainty over the North Pacific and Northern Europe, regions that can modulate but also respond to stratospheric variability, suggesting a two-way propagation of uncertainty. A case study of the 2018 SSW event shows an initial poleward and upward propagation of uncertainty from tropical convection, followed by a downward propagation where ensemble members that accurately predict the SSW also better at predicting its downward impacts. These findings highlight the locations in the troposphere that are linked to stratospheric uncertainty and suggest that improved model representation of tropospheric mechanisms linked to polar vortex variability could enhance both stratospheric and extratropical surface prediction.

Publisher's note: Copernicus Publications remains neutral with regard to jurisdictional claims made in the text, published maps, institutional affiliations, or any other geographical representation in this preprint. The responsibility to include appropriate place names lies with the authors.
Rachel W.-Y. Wu, Gabriel Chiodo, Inna Polichtchouk, and Daniela I. V. Domeisen

Status: open (until 17 Jul 2024)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
Rachel W.-Y. Wu, Gabriel Chiodo, Inna Polichtchouk, and Daniela I. V. Domeisen
Rachel W.-Y. Wu, Gabriel Chiodo, Inna Polichtchouk, and Daniela I. V. Domeisen

Viewed

Total article views: 110 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
75 28 7 110 5 4
  • HTML: 75
  • PDF: 28
  • XML: 7
  • Total: 110
  • BibTeX: 5
  • EndNote: 4
Views and downloads (calculated since 05 Jun 2024)
Cumulative views and downloads (calculated since 05 Jun 2024)

Viewed (geographical distribution)

Total article views: 97 (including HTML, PDF, and XML) Thereof 97 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 12 Jun 2024
Download
Short summary
Strong variations in the strength of the stratospheric polar vortex can profoundly affect surface weather extremes, therefore, accurately predicting the stratosphere can improve surface weather forecasts. The research reveals how uncertainty in the stratosphere is linked to the troposphere. The findings suggest that refining models to better represent the identified sources and impact regions in the troposphere is likely to improve the prediction of the stratosphere and its surface impacts.