The UK’s towns and cities have some of the lowest levels of urban tree cover in Europe, leaving millions of people more exposed to increasingly severe heatwaves, according to new research.
The analysis, published by the Energy and Climate Intelligence Unit (ECIU), found the UK ranks 31st out of 38 European countries for urban tree cover, with only Serbia, Ireland, Kosovo, Montenegro, Malta, Cyprus and Iceland performing worse.
Researchers found the average UK town or city has 17.9% tree cover, compared with a European average of around 30%, while 45 of the 47 UK urban areas included in the study fall below the continental average. None feature among Europe’s top 200 cities for tree canopy.
The report argues that increasing urban tree cover should become a priority as climate change drives more frequent and intense periods of extreme heat.
Urban trees help cool towns and cities by providing shade and through evapotranspiration – the process of releasing water vapour into the air – reducing the so-called urban heat island effect that can make built-up areas several degrees warmer than the surrounding countryside.
The findings come after a series of record-breaking temperatures. June 2026 saw the UK’s hottest June day on record, reaching 37.7°C in Norfolk, while the Met Office issued its first-ever Red Extreme Heat warnings on three consecutive days. Earlier in the year, Kew Gardens recorded the hottest May day ever measured in the UK.
According to the report, cities such as London and Paris are typically around 4°C warmer than nearby rural areas during the night, when excess heat poses the greatest risk to health. During the July 2022 heatwave, modelling suggested temperatures in parts of Greater London were up to 7.2°C higher because of the urban heat island effect.
The report notes that around 370 heat-related deaths occurred in Greater London during that two-week heatwave, with an estimated 38% linked directly to the urban heat island effect.
Researchers say many European cities that regularly experience much hotter summers already have significantly greater tree cover than the UK. Barcelona has around 31% canopy cover, Madrid 29%, Marseille 29% and Nice 39%, compared with London’s 18%.
The study also highlights inequalities in access to urban greenery. Neighbourhoods with the lowest levels of tree cover often experience higher levels of deprivation, pollution and heat exposure, while areas with greater canopy cover have been found to be as much as 4°C cooler during heatwaves than less wooded parts of the same city.
Climate projections suggest the challenge will become more pressing. The Climate Change Committee has warned that the risk of overheating in homes and workplaces could be four times higher by the 2050s, while heat-related hospital admissions are expected to triple.
The ECIU says expanding and maintaining urban tree canopies offers one of the most effective long-term ways of improving resilience to extreme heat, while also delivering wider benefits for biodiversity, air quality and carbon storage. However, it stresses that planting alone is not enough, with mature, well-managed trees providing the greatest cooling benefits as temperatures continue to rise.
Tom Cantillon, Senior Analyst at ECIU said, ‘This recent stream of heatwaves is a stark reminder that climate change is disproportionately hitting the less well-off and vulnerable with less affluent parts of cities more likely to be covered in concrete and heat up more. But they are also the areas least able to afford the tech fixes they never used to need.
‘In the here and now air conditioning to prevent overheating of schools, hospitals and homes of the sick, very young and elderly is clearly needed to try to protect people’s health. But with temperatures set to rise ever higher until we reach net zero emissions and bring balance back to the climate, we need to plan ahead.
‘Planting trees can over time help to bring down temperatures in the buildings they shade, and give more vulnerable people hope of being able to leave their homes into less risky temperatures to do things like shop and visit the GP. The UK is way behind European counterparts, albeit cities like Manchester are in better shape than others.’
The full report can be read here.
Photo: Magdalena Przybyla