Modulation of North Atlantic extratropical cyclones and extreme weather in Europe during North American cold spells ...

• Main Authors: Leeding, Richard, Riboldi, Jacopo, Messori, Gabriele
• Format: Article in Journal/Newspaper
• Language: English
• Published: ETH Zurich 2023
• Subjects: Cold extremes; Extratropical cyclones; Compound extremes; North America; North Atlantic; Europe; North Atlantic storm track
• Online Access: https://dx.doi.org/10.3929/ethz-b-000647852; http://hdl.handle.net/20.500.11850/647852

Recent research has established a statistical link between North American cold spells (CS) and concurrent wet or windy extremes in Europe. Here, we investigate whether such a link can be related to changes in the characteristics of North Atlantic extratropical cyclones (hereafter cyclones). Despite large regions of anomalous baroclinicity during periods of North American CS, the number of cyclones across the North Atlantic as a whole is not significantly above climatology. However, we observe rates of explosive cyclogenesis significantly above climatology. We further find that CS over different North American regions are associated with large-scale atmospheric configurations displaying a strenghtened jet stream in the vicinity of the CS and different upper-level wind anomalies in the East Atlantic. These, in turn, modulate the regional distributions and characteristics of cyclones in the North Atlantic and Europe. We compute a fixed-radius cyclone footprint which we use to associate extreme precipitation and ... : Weather and Climate Extremes, 42 ...