41 percent of people who saw heat alerts took no action, study finds

Heatwaves are becoming more frequent and severe - but a new study finds that 41% of people who saw heat-health alerts in England took no protective action. Why aren't warnings translating into action? This summer's heat has been extreme. Successive heatwaves have dried out landscapes, melted glaciers, shrunk lakes and rivers, while wildfires have scorched vast areas, leaving landscapes dramatically transformed. But the effects of extreme heat go far beyond what we can see in the landscape. And one of the most serious consequences of extreme heat is harder to see: the impact on our health. Despite repeated warnings from health officials, many people in England still do not see extreme heat as a serious health risk. A new investigation by experts at the United Nations University has found a significant gap between heat-health warnings and people's behaviour. The study looked at how people respond to heat-health alerts (HHAs) and why warnings do not always lead to protective action. The researchers surveyed 1,097 adults in England and interviewed 29 people involved in communicating heat risks. What people know does not always translate into action The results reveal a clear gap between what people know about heat and what they actually do about it. Around seven in 10 people surveyed had encountered a Heat Health Alert. But among those who had seen an alert, 41 percent reported taking no action to protect themselves. The most common reason was simple: they did not believe they were personally at risk. Only 18.1 percent of people said they perceived a high risk from extreme heat. Around 30 percent also said they had limited or no knowledge of the actions that could protect them. The reasons for not acting varied. Nineteen percent cited a low perception of their personal risk. Nine percent did not recognise the alert, while 7 percent were unsure what action to take and 5 percent found the alert difficult to understand. So why are people not responding to warnings? The researchers say that simply sending out an alert is not enough. People need to understand that extreme heat can pose a risk to their health, recognise when a warning applies to them and know what they can do to protect themselves. How those warnings are delivered may also be part of the problem. Ninety percent of the heat-risk communicators interviewed said they used digital channels. These allow information to spread quickly, but they do not necessarily reach everyone equally. Social media was identified as the least trusted source of heat information, particularly among older adults. Around 30 percent of people reported not encountering heat-health alerts or heat-protection information at all. That creates a worrying mismatch: the channels used to communicate heat risks do not always reach the people who are most vulnerable to them. How to reach people beyond the digital world The researchers also recommend using trusted local organisations - including community groups, libraries, social care providers, voluntary organisations and faith groups - to reach people who may be missed by digital warnings. The researchers say authorities also need to get better at measuring whether their communication actually works. Instead of simply counting website visits, social media engagement or media coverage, they should assess whether people understand the warnings and whether those warnings lead to protective action. Make heat warnings clearer and more actionable The interviews with heat-risk communicators point to another problem. Heat communication in England is largely focused on coordination between institutions and emergency preparedness, rather than on helping people change their behaviour. The researchers say informing people is currently the dominant objective. But informing alone may not be enough to motivate people to take protective action. And communication is only part of the problem. The study also points to more fundamental factors that determine who is vulnerable to extreme heat. These include housing conditions, socioeconomic disadvantage, existing health problems, environmental exposure and access to resources. A warning cannot address those factors. Beyond warnings: making homes and communities more resilient As heatwaves become more frequent and severe, the researchers argue that England needs to move beyond a predominantly warning-based approach. That means improving how heat risks are communicated, but also making longer-term changes to reduce people's exposure and vulnerability. Housing is a key part of that. The researchers call for heat resilience to be integrated into housing standards, planning policies and retrofit programmes, including stronger implementation and enforcement of measures designed to reduce overheating in buildings. The challenge, the researchers say, is therefore not just to warn people that the next heatwave is coming - but to make sure fewer people are vulnerable when it arrives.