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Analysing the 2021 North American heatwave to understand extraordinary heat events

Investigating the unprecedented 2021 heatwave in the North American Pacific Northwest revealed that a complex interaction between atmospheric dynamics, soil moisture and temperature nonlinearly amplified the event beyond a five-sigma anomaly. These findings may contribute to a better understanding of the physical drivers of future heat extremes.

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Fig. 1: The multivariate drivers and increasing historical likelihood of PNW heatwaves.


  1. Philip, S. Y. et al. Rapid attribution analysis of the extraordinary heatwave on the Pacific Coast of the US and Canada June 2021. Earth Syst. Dyn. (2021). This paper provides an extremely rapid assessment of the 2021 PNW heatwave and quantifies the effect of global warming on the probability of such events.

  2. Neal, E., Huang, C. S. Y. & Nakamura, N. The 2021 Pacific Northwest heat wave and associated blocking: meteorology and the role of an upstream cyclone as a diabatic source of wave activity. Geophys. Res. Lett. 49, e2021GL097699 (2022). This paper attributes sudden blocking-induced mid-atmospheric heating, which helped drive the PNW heatwave, to upstream atmospheric processes.

    Article  Google Scholar 

  3. Fischer, E. M., Sippel, S. & Knutti, R. Increasing probability of record-shattering climate extremes. Nat. Clim. Change 11, 689–695 (2021). This paper finds that extremes that break records by large margins behave statistically differently from smaller extremes, and are increasing in probability.

    Article  Google Scholar 

  4. Rousi, E., Kornhuber, K., Beobide-Arsuaga, G., Luo, F. & Coumou, D. Accelerated western European heatwave trends linked to more-persistent double jets over Eurasia. Nat. Commun. 13, 3851 (2022). This paper finds that jet-stream dynamics are crucial to an emerging hotspot of increasing heat extremes in western Europe.

    Article  CAS  Google Scholar 

  5. McKinnon, K. A. & Simpson, I. R. How unexpected was the 2021 Pacific Northwest heatwave? Geophys. Res. Lett. 49, e2022GL100380 (2022). This paper uses a large ensemble of climate model runs to quantify the probability of a PNW-heatwave-size departure from the mean.

    Article  Google Scholar 

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This is a summary of: Bartusek, S. et al. 2021 North American heatwave amplified by climate change-driven nonlinear interactions. Nat. Clim. Change (2022).

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Analysing the 2021 North American heatwave to understand extraordinary heat events. Nat. Clim. Chang. 12, 1096–1097 (2022).

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