<p>Consistently threatened by climate change, cities need to adapt to emerging hazards and risks. One such risk relates to extreme heat, which is a particular problem in urban areas and is also linked to air pollution. Together, these risks can have a substantial impact on human health. Our analysis of air quality, ambient temperatures, and climate change adaptation plans in 30 UK cities found strong evidence that London and Cambridge exhibit the highest risk of both extreme temperature and air pollution. Furthermore, although a heatwave in London led to lower levels of PM₁₀ and NO₂, it was highly correlated with increased levels of O₃, a low-level pollutant that exacerbates respiratory problems. We also found a lack of data availability (e.g., O₃, PM₁₀) in some local authorities and inconsistencies in their climate change adaptation strategies. We therefore identify a clear need for standardised assessment of hazards at the city level, and their incorporation into local adaptation plans. Further assessment of climate hazards and risks at the city level are required for effectively adapting to a changing climate in the UK and other cities worldwide.</p>