Research from Arup has identified Hackney, Islington and Tower Hamlets as the capital’s most at risk boroughs for vulnerable people during a heat wave.
The three boroughs combine high population density, a large proportion of elderly people with poor health and mobility, and poor quality housing.
Arup’s research comes as London faces its warmest summer on record, with temperatures expected to reach 33°C.
A heat wave is defined as a period where the temperature is higher than the average temperature for that time period by 5°C for five consecutive days.
Satellite images allowed the researchers to map surface temperatures across the capital. The research showed temperature difference of up to 10°C during the summer 2003 heat wave.
“What is interesting about civil engineers is that traditionally they have been focused on flood risks. I think increasingly hot weather risk will become a consideration for them too,” Polly Turton, an environmental consultant at Arup, told New Civil Engineer.
This is thought to be due to the urban heat island effect, which allows a warmer microclimate to build up in areas without trees and green spaces.
Richmond upon Thames, Bromley and Sutton had the lowest risk factors. Hammersmith and Fulham had high temperatures, but these were offset due to the area’s wealth and younger population.
Heat vulnerability map [Arup]
People aged over 65 are the most at risk from heat stroke and exhaustion. Heat waves can make illnesses such as asthma, heart disease and diabetes worse.
“Older people living in cities are a lot more resilient than you might think,” added Turton. She noted that experiences with previous heat waves can make some older people better prepared for the worst.
Heat waves are expected to increase from once every two decades to once every two years by 2050, according to Arup.
“From a practical point of view civil engineers can contribute by considering how green and blue infrastructure can be integrated into civil engineering,” said Turton.
“Simple things like entrances to tube or train stations can make a big difference to people entering infrastructure.”