Without human-caused climate change temperatures of 40oC in the UK would have been extremely unlikely

The 2022 UK heatwave, which saw temperatures reach 40.3°C in Coningsby, was made at least 10 times more likely by human-caused climate change. Observational analysis indicates such an event would have been about 4°C cooler in pre-industrial times, though climate models systematically underestimate this trend. The event had significant impacts on human health, with projected excess mortality of over 840 people in England and Wales, and exposed critical vulnerabilities in UK infrastructure and urban planning.

• Human-caused climate change significantly increased the likelihood of the July 2022 heatwave, making the event at least 10 times more likely for both the 1-day maximum and 2-day average temperature definitions.
• The heatwave was an extreme rarity in the current climate; 2-day average temperatures had a return period of approximately 100 years, while 1-day maximum temperatures over the study region had an estimated return time of 1 in 1000 years.
• Observational data suggests that a UK heatwave of this magnitude would have been approximately 4°C cooler in pre-industrial times, whereas climate models estimate a smaller intensity change of about 2°C in a 1.2°C cooler world.
• The 2022 heatwave resulted in significant human and infrastructure impacts, including projected excess mortality of over 840 people in England and Wales on July 18 and 19, at least 13 drowning deaths, and failures in hospital IT systems due to power outages.
• The UK's vulnerability to extreme heat is exacerbated by unadapted infrastructure, as the country has limited experience with such temperatures and many homes are built to retain heat rather than withstand it.
• Heat impacts were unequally distributed, with poorer neighbourhoods in London experiencing higher temperatures due to a lack of green space, shade, and water.
• Climate models used in the study systematically underestimate observed temperature trends, which leads to conservative estimates of the anthropogenic contribution and reduces confidence in future projections.

APA

Zachariah, M., Vautard, R., Schumacher, D. L., Vahlberg, M., Heinrich, D., Raju, E., Thalheimer, L., Arrighi, J., Singh, R., Li, S., Sun, J., Vecchi, G., Yang, W., Seneviratne, S. I., Tett, S. F. B., Harrington, L. J., Wolski, P., Lott, F. C., McCarthy, M., ... Otto, F. E. L. (n.d.). Without human-caused climate change temperatures of 40oC in the UK would have been extremely unlikely. World Weather Attribution. https://www.worldweatherattribution.org/wp-content/uploads/UK-heat-scientific-report.pdf

Chicago

Zachariah, Mariam, Robert Vautard, Dominik L. Schumacher, Maja Vahlberg, Dorothy Heinrich, Emmanuel Raju, Lisa Thalheimer, et al. Without human-caused climate change temperatures of 40oC in the UK would have been extremely unlikely. World Weather Attribution, n.d. https://www.worldweatherattribution.org/wp-content/uploads/UK-heat-scientific-report.pdf.

Wikipedia

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BibTeX

@techreport{zachariahndwithout, author = {Zachariah, Mariam and Vautard, Robert and Schumacher, Dominik L. and Vahlberg, Maja and Heinrich, Dorothy and Raju, Emmanuel and Thalheimer, Lisa and Arrighi, Julie and Singh, Roop and Li, Sihan and Sun, Jingru and Vecchi, Gabriel and Yang, Wenchang and Seneviratne, Sonia I. and Tett, Simon F. B. and Harrington, Luke J. and Wolski, Piotr and Lott, Fraser C. and McCarthy, Mark and Tradowsky, Jordis S. and Otto, Friederike E. L.}, title = {{Without human-caused climate change temperatures of 40oC in the UK would have been extremely unlikely}}, institution = {World Weather Attribution}, url = {https://www.worldweatherattribution.org/wp-content/uploads/UK-heat-scientific-report.pdf}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }