The United Nations Environment Programme (UNEP) has raised alarm over the growing threat that climate change, particularly extreme heat, poses to older persons around the world. In its newly released Frontiers 2025 Report, UNEP warns that rising temperatures and worsening environmental conditions are putting older adults at significantly greater risk.
Titled “The Weight of Time – Facing a New Age of Challenges for People and Ecosystems,” the 7th edition of the Frontiers Report highlights emerging environmental threats, including heatwaves, melting glaciers, ancient pathogens, and flood-triggered chemical contamination. The report is part of UNEP’s Foresight Trajectory initiative and follows past warnings that have proved prescient, notably its 2016 warning on zoonotic diseases, four years before the COVID-19 pandemic.
“Heatwaves are among the most frequent and deadly impacts of climate change, along with floods and shrinking ice cover,” said UNEP Executive Director Inger Andersen. “We must be prepared for the risks these impacts pose, especially for society’s most vulnerable, including older persons.”
The report comes as countries including China, Japan, India, much of Europe, and the United States are experiencing unprecedented heat and flooding, highlighting the urgent need for inclusive climate resilience strategies.
UNEP notes that adults aged 65 and above are especially vulnerable to climate extremes, particularly in urban centers of low- and middle-income countries. Since the 1990s, annual heat-related deaths among older persons have increased by approximately 85%. Contributing factors include chronic illness, frailty, poor mobility, and limited access to cooling and healthcare, compounded by deteriorating air quality and rising sea levels in coastal cities.
To mitigate these risks, the report calls for cities to be made pollution-free, climate-resilient, and accessible, especially for the ageing population. Recommendations include improved urban planning, expanded green spaces, community-based disaster preparedness, and better access to climate information tailored for older adults.
In a related development, the UN Human Rights Council earlier this year adopted a resolution to develop a legally binding instrument on the human rights of older persons — a step that could strengthen protections for this at-risk demographic amid the worsening climate crisis.
Ancient pathogens and chemical resurgence
The report also warns of a lesser-known climate risk: the reawakening of dormant microbes frozen in glaciers and permafrost. As global temperatures rise beyond 2˚C above pre-industrial levels, the cryosphere—including glaciers, sea ice, and permafrost — is rapidly declining. These frozen regions not only supply water to billions of people but also harbour ancient bacteria, viruses, and fungi, which could emerge and exacerbate antimicrobial resistance.
UNEP recommends urgent emission reductions — including black carbon from diesel engines and wildfires — and greater scientific investment into cryospheric microbiology, while also urging limits on tourism in fragile frozen environments.
Another overlooked danger, according to the report, is the remobilization of banned toxic chemicals. Floods can disturb sediments that have long held harmful pollutants, such as pesticides and industrial compounds, reintroducing them into urban areas and food chains.
To address this, UNEP urges a combination of engineering solutions (e.g., polders, dikes, and retention basins), nature-based interventions such as sponge cities, and regular monitoring of pollutants in vulnerable regions.
Ageing dams: A growing infrastructure risk
The report also draws attention to ageing dams, which pose safety hazards and environmental challenges. While dams have long supported agriculture and hydropower, many are now obsolete or unsafe. Their removal, already underway in parts of Europe and North America, could restore natural river ecosystems, boost biodiversity, and support the UN’s ecosystem restoration goals.
The Frontiers 2025 Report concludes that while the world faces mounting environmental threats, many solutions already exist — if action is taken urgently and equitably.
“This is a critical moment for governments, cities, and communities to rethink how we care for our most vulnerable people and ecosystems,” Andersen said. “We must not only adapt to climate change but also transform the systems that continue to leave people behind.”
