Chantelle A Burton, Andrew Ciavarella, Douglas Ian Kelley , Andrew Hartley, Mark Mccarthy, Stacey New, Richard A Betts, Eddy Robertson

The UK experienced an unprecedented heatwave in 2022, with temperatures reaching 40°C for the first time in recorded history. This extreme heat was accompanied by widespread fires across London and elsewhere in England, which destroyed houses and prompted evacuations. While attribution studies have identified a strong human fingerprint contributing to the heatwave, no studies have attributed the associated fires to anthropogenic influence. In this study, we assess the contribution of human-induced climate change to fire weather conditions over the summer of 2022 using simulations from the HadGEM3-A model with and without anthropogenic emissions, and apply the Canadian Fire Weather Index. Our analysis reveals at least a 6-fold increase in the probability of very high fire weather in the UK due to human influence, most of which is driven by high fire conditions across England. These findings highlight the significant role of human-induced climate change in the emerging threat of wildfires in the UK. As we experience more hotter and drier summers as temperatures continue to rise, the frequency and severity of fires are likely to increase, posing significant risks to both natural ecosystems and human populations. This study underscores the need for further research to quantify the changing fire risk due to our changing climate, and the urgent requirement for mitigation and adaptation efforts to address the growing wildfire threat in the UK.