Richmond Hill, Ontario, Canada (14 August 2026) — As temperatures continue to soar and amber heat-health alerts are issued across England, warnings are reaching the public but still failing to change behaviour. A new investigation by the United Nations University experts finds that among adults in England who saw a Heat Health Alert, 41% took no action to protect themselves. The most common reason was not confusion or inconvenience. It was that they did not believe heat put them at risk.
Drawing on a national survey of adults and interviews with experts responsible for communicating heat risk in England, Strengthening England’s Heat Resilience: From Warnings to Long-Term Adaptation , published by the UN University’s Institute for Water, Environment and Health ( UNU-INWEH ), examines whether England’s warning system translates into protective behaviour.
England’s warnings were tested severely this summer. On 26 June, the country recorded a provisional maximum of 37.7°C at Lingwood, Strumpshaw Hill, breaking a June record that had stood since 1976, while England was placed under only the second Red Heat Health Alert in the system’s history. Nights brought little relief, with a new June minimum of 23.2°C recorded at Hastings, limiting the overnight recovery that helps reduce the health impacts of daytime heat, particularly for older adults. The pressure returned in August, as another spell of extreme heat prompted widespread amber health alerts across England, with temperatures again reaching levels that posed significant risks to health, particularly for older adults.
The survey results suggest that seven in ten people encountered a Heat Health Alert. Among them, 41% did nothing to protect themselves. The reason given most often was that they did not see themselves as personally at risk. Some did not recognise what they were looking at when it came to the alert, while others were unsure what they were supposed to do or found the alert hard to understand.
The UN University publication explains why. Only 18% of people in England report a high perception of heat risk, and around 30% say they know little or nothing about the actions that would protect them. A similar percentage had come across no alerts or heat protection information at all, a separate group from those who saw the information and did not know what to do with it. The system leans heavily on digital channels, which spread information fast but reach unevenly, and social media was the least trusted source of heat information, particularly among older adults. The channels carrying the warning are often the ones least likely to reach the people most vulnerable to heat.
“People aren’t ignoring these alerts because they don’t care,” said Dr Mehri Khosravi , Research Fellow, Behavioural Change and Risk Communication at UNU-INWEH and lead author of the Policy Brief. “They read them and think, this isn’t about me. Heat still gets treated as good weather, or as something that only happens to the very old and the very ill. Until that changes, we can send perfect warnings and watch very little happen.”
Interviews with the heat risk experts describe a system built for institutions rather than households. Informing the public was not the dominant communication objective, cited by 76% of interviewed practitioners, with far less emphasis on motivating action or enabling it. Communication does most of its work coordinating national agencies, local authorities, health services and emergency responders once a heatwave is under way.
The publication argues that the deeper problem lies outside the alerting system altogether. Housing conditions, deprivation, existing health problems and environmental exposure shape who suffers in a heatwave, and none of them are addressed by a warning. International guidance holds that a heat health action plan should pair short-term alerts with long-term measures that reduce vulnerability, yet England’s approach remains weighted towards the warning component.
To close that gap, the authors call for heat resilience to be built into housing standards, planning policy and retrofit programmes, with stronger enforcement and implementation of Part O of the Building Regulations. They also call for investment in the institutional capacity of local authorities and community organisations, and for wider use of trusted intermediaries such as libraries, faith groups, voluntary organisations and social care providers to reach people that digital channels miss. Few organisations currently measure whether their communication changes behaviour, and the brief argues that evaluation should track whether alerts prompt protective action rather than how many people saw them.
“A warning tells you a heatwave is coming. It doesn’t tell you how to get through the night in a flat that traps heat,” said Professor Kaveh Madani , Director of UNU-INWEH and a co-author of the Policy Brief. “England has built one half of a heat plan, and built it well. The other half is where people actually live. That is where the next decade of work has to go.”
Read the Policy Brief
Khosravi, M., Assan, A. and Madani, K. (2026). Strengthening England’s Heat Resilience: From Warnings to Long-Term Adaptation. United Nations University Institute for Water, Environment and Health (UNU-INWEH), Richmond Hill, Ontario, Canada. doi: 10.53328/INP26PMK001
Support Paper: Assan, A. A., Khosravi, F. and Osei, G. (2026). The heat is on: Understanding public responses to heat-health alerts in England. Energy Research & Social Science, 135, 104685.
Available for Interview: Interview requests should be submitted to media.inweh@unu.edu
About UNU-INWEH
Marking its 30th anniversary of operation in 2026, the United Nations University Institute for Water, Environment and Health ( UNU-INWEH ) is one of 13 institutions that make up the United Nations University ( UNU ), the academic arm of the UN. Known as ‘The UN’s Think Tank on Water’, UNU-INWEH addresses critical water, environmental, and health challenges around the world. Through research, training, capacity development, and knowledge dissemination, the institute contributes to solving pressing global sustainability and human security issues of concern to the UN and its Member States. Headquartered in Richmond Hill, Ontario, UNU-INWEH has been hosted and supported by the Government of Canada since 1996. With a global mandate and extensive partnerships across UN entities, international organizations, and governments, UNU-INWEH operates through its UNU Hubs in Calgary, Hamburg, New York, Lund, and Pretoria, and an international network of affiliates.
Strengthening England’s Heat Resilience: From Warnings to Long-Term Adaptation
14-Aug-2026