Why heat deaths occur during low-level alerts - UEL study

Based on a nationally representative survey of more than 1,000 adults in England, the research highlights widespread gaps in awareness, understanding and response to heat health alerts.

Key findings include:

• Nearly one in three people (30%) had not received a heat-health alert at all
• Over 40% of those who had received alerts said they ignored them
• Only 25% said they would act on yellow alerts, compared to a much higher response to red warnings
• Older adults (65+) were among the least likely to take action unless alerts reached the highest level 

Older people - who account for more than 90% of heat-related deaths - are also among those least likely to respond to lower-level alerts, suggesting those most at risk may be missing critical opportunities to protect themselves.

The research also highlights inequalities in who receives and engages with alerts, with older adults and lower-income groups less likely to encounter warnings in the first place, pointing to gaps in reach and digital exclusion.

Beyond awareness, the study found that many people do not perceive heat as a serious personal risk, or lack clear guidance on what action to take. Misunderstanding of alert levels is common, and unclear messaging may be contributing to widespread inaction.

Researchers warn that the current system risks creating a false sense of security during lower-level alerts, when people are less likely to act despite real and present dangers.

Dr Mehri Khosravi, Senior Research Fellow at UEL’s Sustainability Research Institute and lead author of the study, said,

Too many people are not seeing, not understanding, or not acting on heat alerts – and that is putting lives at risk. Lower-level warnings in particular are being overlooked, despite posing real danger.”

She added, “We need to rethink how we communicate heat risk, especially with the elderly who are mostly digital exclusive. Alerts must be clearer, more relevant and more actionable, especially for those most vulnerable, if they are to prevent avoidable deaths.”

The research, entitled The heat is on: Understanding public responses to heat-health alerts in England, co-authored by Dr Mehri Khosravi, Angela Afua Assan, and Dr Gloria Osei, is published in Energy Research & Social Science.

Image by Daniela Paola Alchapar on Unsplash.

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