Persistent Summer Extremes – PERSIST (2018-2022)

Summer extremes are particularly devastating when they persist for several days: many consecutive hot-and-dry days causing harvest failure, or stagnating wet extremes causing flooding. Despite this importance, persistence of extreme summer weather has largely been neglected by the climate science community.

  • What maintains stagnating summer weather?
  • Do climate models capture the underlying processes accurately?
  • What is the role of global warming?

Persistence is linked to sea-surface temperature, soil moisture and atmospheric circulation which are expected to change with future warming but the uncertainties are large.

Figure Persist

This study was conducted in collaboration with KNMI.

Contact information: Dim Coumou, Fei Luo and Sem Vijverberg.

For more information, please visit the site


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  • Kornhuber, K. et al. (2019). Amplified Rossby waves enhance risk of concurrent heatwaves in major breadbasket regions. Nature Climate Change.
  • Pfleiderer, P. et al. (2019). Summer weather becomes more persistent in a 2°C world. Nature Climate Change.