Expert Comment: Heatwaves are social disasters in England
Shiv Yucel, a DPhil candidate in the Transport Studies Unit at the University of Oxford, explains why heatwaves hit some groups far harder than others, and what his research on everyday travel behaviour reveals about the inequalities that shape who is most at risk.
As forecasters point to a return to heatwave conditions in the coming days, the UK is counting the cost of a record-breaking summer. The UK's June temperature record, which had stood since 1957, was broken on three consecutive days, reaching a provisional 37.7°C, and England recorded its warmest June on record.
Such heat is becoming less exceptional: the Met Office reports that heatwaves are rising in frequency and intensity across the UK, while Copernicus and the World Meteorological Organization find that Europe, the fastest-warming continent, faces more frequent and more intense summer heat.
In England, a country where heat has historically been of little concern, millions of overheating homes and more than 1,500 heat-related deaths in 2025 are rapidly changing how we think about extreme temperatures.
As heatwaves become a regular feature of British summers, the pressing question is who is most exposed when temperatures climb, and who is least able to cope. Beyond physiological factors alone, heatwaves are also known as social disasters because their impacts are shaped by existing social (e.g. age) and material (e.g. income) inequalities.
“People with mobility difficulties, defined as having impairments which limit abilities to walk, use public transport, or drive, are more likely to withdraw into their homes. While this may represent a protective response that limits outdoor exposure, it may also indicate barriers to accessing healthcare, cooler public spaces, or other forms of support during extreme heat.”
Mobility data as a lens to understand summer heatwave adaptation
Many behaviours related to exposure and adaptation relate to where people go and spend their time when dangerous temperatures occur. By using mobility data from past disasters, we can understand how heat risks unfold within the context of people’s daily lives and inequalities in how people adapt.
My latest study focuses on England, using 13 years of data from the National Travel Survey (2007-2019). It examines two key behaviours during summer heatwaves: sheltering at home rather than going out, and seeking medical services. Here, a heatwave is defined as two or more consecutive days of extreme temperatures above regional norms, graded as 'moderate' or 'extreme' depending on whether it falls in the bottom 70% or top 30% of intensity for that region. The study analyses how these behaviours vary while accounting for factors such as age, gender, health, income, employment, housing, and residential location.
Overall, people tend to remain slightly more active during moderate heatwaves in England, but increasingly shelter at home during extreme heatwaves. However, these general tendencies mask important differences in how people respond.
People with mobility difficulties, defined as having impairments which limit abilities to walk, use public transport, or drive, are more likely to withdraw into their homes. While this may represent a protective response that limits outdoor exposure, it may also indicate barriers to accessing healthcare, cooler public spaces, or other forms of support during extreme heat. For those unable to adequately cool at home, accessible cooling centres in libraries, community centres, and other public buildings will become increasingly important measures. These services – which are currently not in national UK heatwave plans – should also account for people with mobility difficulties through transport assistance and bolstered community support networks.
Healthy older adults tend to remain more active during moderate heatwaves than the general population, which is associated with increased trips to medical services. This may result from an underestimation of risk during what might be considered pleasant weather. Heatwaves are too often visually portrayed using 'fun in the sun' imagery without due attention to their dangerous public health consequences, and older individuals, who are among the most vulnerable to heatwaves, commonly underestimate their risk in England.
People with routine and manual occupational backgrounds are less likely than the general population to shelter at home during extreme heatwaves. These workers are among the most vulnerable to heat stress due to heat exposure and physically demanding work. Compared to workers who can easily adjust their hours or work remotely, inflexible workplace requirements may limit their ability to reduce heat exposure. Unlike several European countries, the UK has no maximum safe working temperatures. Introducing context- and occupation-specific heat protections, alongside greater flexibility in working hours during extreme heat events, is an important measure to protect those in heat-exposed occupations.
Housing conditions also shape vulnerability. Home renters make more trips for healthcare services during extreme heatwaves than homeowners. Renters experience higher rates of home overheating in the UK and have less autonomy to install cooling measures or adapt their homes to reduce overheating. Housing policy must become a cornerstone of heat adaptation. England's housing stock was not designed with extreme heat in mind, leaving many homes without key heat-protective components such as shutters over windows. Retrofitting homes with effective shading, ventilation, and other heat-resilient measures is increasingly necessary. Because tenants often lack the ability to make these changes themselves, future policy should place greater responsibility on landlords to ensure rented homes remain safe during extreme heat.
The study also reveals ethnic inequalities in heatwave responses. Non-White individuals are less likely than White individuals to make medical trips in general, and this disparity tends to widen during extreme heatwaves. Previous research has shown that ethnic minority communities experience higher rates of home-overheating and heat-related mortality in England; these findings suggest that their barriers to accessing healthcare – including language, cultural factors, and interactions with healthcare systems – may contribute to these unequal outcomes.
People adapting their everyday lives to heatwaves is not specific to England; it occurs in widely different ways across different parts of the world. Our prior research using mobile phone location data has shown the extent to which people adapt their everyday lives to cope with the threat of summer heatwaves.
In a study of the Pacific Northwest coast of North America, people in more temperate and less air-conditioned locations (e.g. British Columbia) rely more on out-of-home cooling – substituting time at home and visits to the workplace. This contrasts with widespread home-withdrawal in typically hotter and more air-conditioned places (e.g. California). We observed that income inequalities mediate how people adapt, with greater visitation to parks in lower-income counties where people may own less air conditioning or not be able to afford to use it.
Our subsequent study then showed that these ‘everyday adaptations’ are global in scale, with diverse changes to daily activities occurring across seven of the most at-risk countries to heatwaves (Brazil, France, India, Nigeria, Turkey, United States, China). Across countries with widely varying income levels, air conditioning ownership rates, and heat policy preparedness, people are already adapting their daily lives to cope with the threat of summer heatwaves.
By studying where people go and spend their time during summer heatwaves, this area of research helps uncover how these ‘silent killers’ prey on existing social and material inequalities.
For more information about this story or republishing this content, please contact [email protected]
