Extreme heat is no longer just an uncomfortable season to endure it has quietly become one of the deadliest and least addressed climate hazards of our time. In a high-level event held at the 2025 Global Platform for Disaster Risk Reduction, leaders from governments, global agencies, labor unions, academia, and humanitarian organizations came together to sound the alarm: the world must radically rethink how it prepares for and manages the rising danger of extreme heat.
“Extreme heat is the deadliest of all climate-related hazards,” warned Celeste Saulo, Director-General of the World Meteorological Organization (WMO). “Yet it remains the least recognized and least managed.”
A Growing, Silent Threat
The numbers are stark. Between 2000 and 2019, extreme heat contributed to nearly half a million deaths every year worldwide. The economic toll is rising too, especially in low- and middle-income countries, where the International Labour Organization (ILO) estimates that excessive heat at workplaces can cost up to 1.5% of national GDP. And this danger is growing faster than ever.
“This is no longer just a health issue—it’s an economic, labor, and governance crisis,” Dr. Saulo stressed.
Yet as of 2023, only half the world’s national weather agencies were issuing heat warnings, and just 26 countries had specialized heat-health early warning systems in place, according to WMO data.
The danger is worse in cities, where urban areas are warming at twice the global average rate. With two-thirds of the global population expected to live in cities by 2050, the risks are only set to intensify.
From Warnings to Systemic Change
Current responses to heat risks are largely reactive: authorities issue warnings when temperatures spike, hospitals brace for patients, and the economic damage is counted after the fact. But experts insist this piecemeal approach is no longer enough.
“Heat is a systemic risk that touches everything—public health, economic stability, food security, and energy supply,” said Dr. Pramod Kumar Mishra, Principal Secretary to the Prime Minister of India. “The problem is not technical—it’s the lack of effective planning and policies.”
“Most of the impacts of extreme heat are predictable,” added Jagan Chapagain, Secretary General of the International Federation of Red Cross and Red Crescent Societies (IFRC). “And if they are predictable, they are preventable.”
For real protection, governments need to act in advance—designing cities, workplaces, and infrastructure that can withstand heat stress while safeguarding the poorest and most vulnerable.
Local Lessons, Global Models
Several countries are showing the way:
•India began its heat planning journey in Ahmedabad, Gujarat and now boasts over 250 cities and districts with active Heat Action Plans.
•France transformed its policies after the tragic 2003 heatwave, forcing every ministry to plan for a future where +4°C scenarios are real possibilities.
•The Philippines launched “iHeatMap,” a real-time monitoring tool, and set up a cross-agency task force to tackle heat’s impacts on food, water, and energy supplies.
•The Making Cities Resilient 2030 initiative has also issued practical guidance for urban heat risk management, supporting cities in building long-term resilience.
But experience alone is not enough, warned Canadian Senator Rosa Galvez. Reflecting on the 2021 “heat dome” event in British Columbia which killed 618 people—she said: “We cannot keep adapting forever. We have to reduce the risk itself.”
Protecting the Poorest First
The burden of extreme heat falls hardest on the poor, warned Mia Seppo of the ILO. Informal workers, slum dwellers, and low-income families cannot afford air conditioners—or poor urban planning.
“Financial flows must align with climate justice,” Seppo said. “Every development project must consider heat risk—not just for the buildings, but for the workers building them.”
French climate ambassador Benoît Faraco agreed, calling for strict building codes and design standards that factor in climate risks. Without these rules, he warned, markets would respond with short-term fixes—like a rush to air conditioning—that could worsen the climate crisis.
“You can’t build hospitals and schools today as if the climate wasn’t changing,” he said. “Good regulation prevents bad adaptation.”
A Global Framework for Local Action
To guide countries, the UNDRR, WHO, WMO, and the Global Heat Health Information Network are developing a Common Framework for Extreme Heat Risk Governance. This will help cities and countries include heat risks in every part of disaster planning, climate policy, and public health strategy.
The framework will support the UN’s eight-point Call to Action on Extreme Heat, which urges governments to:
•Shift to renewable energy.
•Invest in climate-resilient energy systems.
•Promote heat-resilient farming.
•Strengthen food supply chains.
•Design cooler, greener cities.
•Use nature-based solutions.
•Implement Heat Action Plans and early warning systems.
•Ensure heat-safe workplaces.
“The tools exist. The science is clear. We just need urgent, coordinated action,” said Celeste Saulo.
Every Heat Death is Preventable
Closing the event, UN disaster chief Kamal Kishore issued a bold call: aim for zero heat deaths next summer.
“We dream of 100,000 heat-resilient schools within five years,” he said. “We know how to build them with shade, ventilation, green space, and water. It’s not rocket science. But it takes political will.”
The new Common Framework could turn this vision into reality if governments, businesses, and communities act fast.
“Extreme heat is no longer tomorrow’s problem,” said Kishore. “It’s today’s emergency. And every day we delay costs lives.”