Summer weather becomes more persistent in a 2 °C world

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Heat and rainfall extremes have intensified over the past few decades and this trend is projected to continue with future global warming1,2,3. A long persistence of extreme events often leads to societal impacts with warm-and-dry conditions severely affecting agriculture and consecutive days of heavy rainfall leading to flooding. Here we report systematic increases in the persistence of boreal summer weather in a multi-model analysis of a world 2 °C above pre-industrial compared to present-day climate. Averaged over the Northern Hemisphere mid-latitude land area, the probability of warm periods lasting longer than two weeks is projected to increase by 4% (2–6% full uncertainty range) after removing seasonal-mean warming. Compound dry–warm persistence increases at a similar magnitude on average but regionally up to 20% (11–42%) in eastern North America. The probability of at least seven consecutive days of strong precipitation increases by 26% (15–37%) for the mid-latitudes. We present evidence that weakening storm track activity contributes to the projected increase in warm and dry persistence. These changes in persistence are largely avoided when warming is limited to 1.5 °C. In conjunction with the projected intensification of heat and rainfall extremes, an increase in persistence can substantially worsen the effects of future weather extremes.

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Fig. 1: Illustration of the persistence metrics.
Fig. 2: Persistence climatology for the NH mid-latitudes in JJA.
Fig. 3: Relative change in exceedance probability in JJA in HAPPI models.
Fig. 4: Drivers of changes in persistence.
Fig. 5: Relative change in exceedance probability distributions for 2 °C and 1.5 °C worlds versus 2006–2015 in HAPPI models.

Data availability

The observational data and HAPPI simulations that support the findings of this study are publicly available online at, and

Code availability

Python scripts used for the analysis are available on


  1. 1.

    Coumou, D., Robinson, A. & Rahmstorf, S. Global increase in record-breaking monthly-mean temperatures. Climatic Change 118, 771–782 (2013).

  2. 2.

    Lehmann, J., Mempel, F. & Coumou, D. Increased occurrence of record-wet and record-dry months reflect changes in mean rainfall. Geophys. Res. Lett. 45, 13468–13476 (2018).

  3. 3.

    IPCC Climate Change 2013: The Physical Science Basis (eds Stocker, T. F. et al.) (Cambridge Univ. Press, 2013).

  4. 4.

    Petoukhov, V. et al. Alberta wildfire 2016: apt contribution from anomalous planetary wave dynamics. Sci. Rep. 8, 12375 (2018).

  5. 5.

    Kornhuber, K. et al. Extreme weather events in early summer 2018 connected by a recurrent hemispheric wave-7 pattern. Environ. Res. Lett. 14, 054002 (2019).

  6. 6.

    Erntebericht 2018 (BMEL, 2018);

  7. 7.

    Deutschlandwetter im Sommer 2018 (DWD, 2018);

  8. 8.

    Stadtherr, L., Coumou, D., Petoukhov, V., Petri, S. & Rahmstorf, S. Record Balkan floods of 2014 linked to planetary wave resonance. Sci. Adv. 2, e1501428 (2016).

  9. 9.

    van Oldenborgh, G. J. et al. Rapid attribution of the May/June 2016 flood-inducing precipitation in France and Germany to climate change. Hydrol. Earth Syst. Sci. Discuss. (2016).

  10. 10.

    Perkins-Kirkpatrick, S. E. & Gibson, P. B. Changes in regional heatwave characteristics as a function of increasing global temperature. Sci. Rep. 7, 1–12 (2017).

  11. 11.

    O. Hoegh-Guldberg, et al. in Global Warming of 1.5°C (eds Masson-Delmotte, V. et al.) 175–312 (IPCC, WMO, in the press).

  12. 12.

    Pfleiderer, P. & Coumou, D. Quantification of temperature persistence over the Northern Hemisphere land-area. Clim. Dynam. 51, 627–637 (2018).

  13. 13.

    Francis, J. A., Skific, N. & Vavrus, S. J. North American weather regimes are becoming more persistent: is Arctic amplification a factor? Geophys. Res. Lett. 45, 11,414–11,422 (2018).

  14. 14.

    Horton, D. E. et al. Contribution of changes in atmospheric circulation patterns to extreme temperature trends. Nature 522, 465–469 (2015).

  15. 15.

    Hoffmann, P. Enhanced seasonal predictability of the summer mean temperature in Central Europe favored by new dominant weather patterns. Clim. Dynam. 50, 2799–2812 (2018).

  16. 16.

    Alvarez-Castro, M. C., Faranda, D. & Yiou, P. Atmospheric dynamics leading to west European summer hot temperatures since 1851. Complexity 2018, 1–10 (2018).

  17. 17.

    Mitchell, D. et al. Half a degree additional warming, prognosis and projected impacts (HAPPI): background and experimental design. Geosci. Model Dev. 10, 571–583 (2017).

  18. 18.

    Dosio, A., Mentaschi, L., Fischer, E. M. & Wyser, K. Extreme heat waves under 1.5 °C and 2 °C global warming. Environ. Res. Lett. 13, 054006 (2018).

  19. 19.

    Zhang, X. et al. Indices for monitoring changes in extremes based on daily temperature and precipitation data. WIREs Clim. Change 2, 851–870 (2011).

  20. 20.

    Zscheischler, J. et al. Future climate risk from compound events. Nat. Clim. Change 8, 469–477 (2018).

  21. 21.

    IPCC Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation (eds Field, C.B. et al.) (Cambridge Univ. Press, 2012).

  22. 22.

    Coumou, D., Di Capua, G., Vavrus, S., Wang, L. & Wang, S. The influence of Arctic amplification on mid-latitude summer circulation. Nat. Commun. 9, 2959 (2018).

  23. 23.

    Mann, M. E. et al. Projected changes in persistent extreme summer weather events: the role of quasi-resonant amplification. Sci. Adv. 4, eaat3272 (2018).

  24. 24.

    Coumou, D., Lehmann, J. & Beckmann, J. The weakening summer circulation in the Northern Hemisphere mid-latitudes. Science 348, 324–327 (2015).

  25. 25.

    Lehmann, J., Coumou, D., Frieler, K., Eliseev, A. V. & Levermann, A. Future changes in extratropical storm tracks and baroclinicity under climate change. Environ. Res. Lett. 9, 084002 (2014).

  26. 26.

    Hirschi, M. et al. Observational evidence for soil-moisture impact on hot extremes in southeastern Europe. Nat. Geosci. 4, 17–21 (2011).

  27. 27.

    Donat, M. G., Pitman, A. J. & Angélil, O. Understanding and reducing future uncertainty in midlatitude daily heat extremes via land surface feedback constraints. Geophys. Res. Lett. 45, 10,627–10,636 (2018).

  28. 28.

    Lesk, C., Rowhani, P. & Ramankutty, N. Influence of extreme weather disasters on global crop production. Nature 529, 84–87 (2016).

  29. 29.

    Donat, M. G. et al. Global land-based datasets for monitoring climatic extremes. Bull. Am. Meteorol. Soc. 94, 997–1006 (2013).

  30. 30.

    Haylock, M. R. et al. A European daily high-resolution gridded data set of surface temperature and precipitation for 1950-2006. J. Geophys. Res. Atmos. 113, D20119 (2008).

  31. 31.

    Meyer-Christoffer, A., Becker, A., Finger, P., Schneider, U. & Ziese, M. GPCC Climatology Version 2018 at 1.0° (GPCC, 2018);

  32. 32.

    Dee, D. P. et al. The ERA-Interim reanalysis: configuration and performance of the data assimilation system. Q. J. R. Meteorol. Soc. 137, 553–597.

  33. 33.

    Zolina, O., Simmer, C., Belyaev, K., Gulev, S. K. & Koltermann, P. Changes in the duration of European wet and dry spells during the last 60 years. J. Clim. 26, 2022–2047 (2013).

  34. 34.

    Murakami, M. Large-scale aspects of deep convective activity over the GATE area. Mon. Weather Rev. 107, 994–1013 (1979).

  35. 35.

    McKee, T. B., Doesken, N. J. & Kleist, J. The relationship of drought frequency and duration to time scales. In Proc. Eighth Conference on Applied Climatology 179–184 (American Meteorological Society, 1993).

  36. 36.

    Vicente-Serrano, S. M., Beguería, S. & López-Moreno, J. I. A multiscalar drought index sensitive to global warming: the standardized precipitation evapotranspiration index—SPEI. J. Clim. 23, 1696–1718 (2010).

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The authors would like to thank the HAPPI initiative and all participating modelling groups that have provided data. This research used science gateway resources of the National Energy Research Scientific Computing Center, a Science User Facility supported by the Office of Science of the US Department of Energy under contract no. DE-AC02-05CH11231. We thank the Met Office Hadley Centre for providing the HadGHCND dataset. We acknowledge the E-OBS dataset from the EU-FP6 project ENSEMBLES ( and the data providers in the ECA&D project ( P.P. and C.-F.S. acknowledge support by the German Federal Ministry of Education and Research (01LN1711A). K.K. is supported by the UK NERC, NCAS and NERC grant nos NE/P006779/1 and NE/N018001/1. This work was supported by the BMBF (grant no. 01LN1304A to D.C.) and the NWO (grant no. 016.Vidi.171011 to D.C.).

Author information

P.P., C.-F.S., K.K. and D.C. conceived the study. P.P. analysed the data. P.P. wrote the manuscript with contributions from all authors.

Correspondence to Peter Pfleiderer.

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The authors declare no competing interests.

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Peer review information: Nature Climate Change thanks Peter Gibson and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Supplementary Figs. 1–9 and Tables 1–4.

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