Validation of boreal summer tropical–extratropical causal links in seasonal forecasts

Di Capua, Giorgia; Coumou, Dim; van den Hurk, Bart; Weisheimer, Antje; Turner, Andrew G.; Donner, Reik V.

doi:https://doi.org/10.5194/wcd-4-701-2023

Articles | Volume 4, issue 3

https://doi.org/10.5194/wcd-4-701-2023

© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

https://doi.org/10.5194/wcd-4-701-2023

© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 4, issue 3

Research article

|

14 Aug 2023

Research article |

| 14 Aug 2023

Validation of boreal summer tropical–extratropical causal links in seasonal forecasts

Giorgia Di Capua, Dim Coumou, Bart van den Hurk, Antje Weisheimer, Andrew G. Turner, and Reik V. Donner

Supplement

https://doi.org/10.5194/wcd-4-701-2023-supplement

Data sets

Seasonal forecast subdaily data on pressure levels Copernicus Climate Change Service, Climate Data Store https://doi.org/10.24381/cds.50ed0a73

ERA5 hourly data on single levels from 1940 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.adbb2d47

Short summary

Heavy rainfall in tropical regions interacts with mid-latitude circulation patterns, and this interaction can explain weather patterns in the Northern Hemisphere during summer. In this analysis we detect these tropical–extratropical interaction pattern both in observational datasets and data obtained by atmospheric models and assess how well atmospheric models can reproduce the observed patterns. We find a good agreement although these relationships are weaker in model data.