The surprising reason parks feel so much cooler than city streets, according to Leeds Uni scientists
The study looks at the impact of urban tree cover - and how they help to keep cities cool
Trees and parks across Leeds are doing far more than making the city look greener - they’re helping to protect residents from extreme heat.
As temperatures continue to rise, a new study from researchers at the University of Leeds and Leeds Beckett University found that urban treescapes can be up to 6C cooler than nearby built-up areas during hot weather.
The study has been published in People and Nature as part of Dr Jim Parker’s Future of UK Treescapes Fellowship funded by UK Research and Innovation (UKRI).
Dr Cat Scott from the University of Leeds School of Earth, Environment, and Sustainability, who was a co-author on the paper, said: “A key part of making our towns and cities more resilient will be to improve people's access to cooler spaces.
“As our findings suggest, the protection and expansion of urban tree cover is a key strategy for improving public health, thermal comfort, and the climate resilience of our towns and cities.
"We need to take the role of trees and green spaces in our towns and cities more seriously – these aren't just nice-to-have, they are critical infrastructure.”
The researchers installed a network of sensors across Leeds, measuring air temperature and humidity every 15 minutes through the summers of 2023 and 2024.
The sensors were on busy streets, small city centre parks, larger suburban parks, and different types of treescapes such as larger woodlands or small groups of trees.
One sensor was installed in a mature tree at the University of Leeds Gair Wood site in north Leeds, providing a rural treescape dataset for the study.
By comparing conditions across these locations, the researchers were able to explore how temperatures varied during warm summer periods.
The cooling ability of trees is due to the shade they provide and the process of evapotranspiration – where trees take water from below the ground via their roots, transport it through their tissues and out through tiny holes on their leaves. Once at the leaf surface, water can evaporate, which cools down the surrounding air.
Professor Jim McQuaid at the University of Leeds School of Earth, Environment and Sustainability, who co-authored the research, said: “We are already seeing the impacts of climate change on summertime temperatures in the UK.
“This summer has seen records smashed across the UK, with four heatwaves already on the books this year. We are looking forward to analysing the most recent data from the sensor network which continues to provide a highly detailed map of the temperatures across the city.”
Dr Jim Parker from Leeds Beckett University, who led the study, concludes: “Our evidence shows that planting and protecting trees is a practical and effective way to make cities safer, healthier and more comfortable, especially as our climate continues to warm.”