The World Health Organization (WHO) has unveiled new guidance for governments seeking to protect people from extreme heat, a growing priority as climate change pushes temperatures higher worldwide and intensifies heatwaves and related health risks.
The launch came as the US National Oceanic and Atmospheric Administration said on Thursday that El Niño has developed in the tropical Pacific. The climate phenomenon – which occurs naturally every few years – is predicted to intensify to a moderate or strong level this autumn, the service said.
Scientists have warned that a strong El Niño weather pattern could fuel “unprecedented” weather extremes in the coming months, including severe fires and droughts, and may make 2027 the next record-breaking hot year as it supercharges human-driven warming.
Scientists warn El Niño could intensify climate extremes in 2026
Unveiling updated recommendations for “Heat-Health Action Plans”, which are tailored for Europe but can be adapted globally, Hans Henri P. Kluge, WHO’s regional director for Europe, said that over the past four years, heat has claimed more than 200,000 lives across 32 European countries.
Already have an account?
Log in here →
Climate Home News is on the ground in Bonn — one of the few outlets covering the negotiations that will shape COP31 in November.
Join free and keep reading →
It takes less than a minute.
The World Health Organization (WHO) has unveiled new guidance for governments seeking to protect people from extreme heat, a growing priority as climate change pushes temperatures higher worldwide and intensifies heatwaves and related health risks.
The launch came as the US National Oceanic and Atmospheric Administration said on Thursday that El Niño has developed in the tropical Pacific. The climate phenomenon – which occurs naturally every few years – is predicted to intensify to a moderate or strong level this autumn, the service said.
Scientists have warned that a strong El Niño weather pattern could fuel “unprecedented” weather extremes in the coming months, including severe fires and droughts, and may make 2027 the next record-breaking hot year as it supercharges human-driven warming.
Scientists warn El Niño could intensify climate extremes in 2026
Unveiling updated recommendations for “Heat-Health Action Plans”, which are tailored for Europe but can be adapted globally, Hans Henri P. Kluge, WHO’s regional director for Europe, said that over the past four years, heat has claimed more than 200,000 lives across 32 European countries.
He added that most of those deaths were “entirely preventable” and are “just the tip of the iceberg”, with millions more people being affected physically and mentally by the effects of extreme heat. Scientists have said Europe is the fastest-warming continent.
“Individual action, such as keeping out of the heat, keeping our homes cool and keeping our bodies hydrated, can make a big difference in protecting us, but it is not enough to fight a systemic crisis,” Kluge said in a statement. “We need a coordinated, powerful and institutional response.”
The new guidance focuses on the importance of providing early warning and alerts, targeting vulnerable groups and putting in place longer-term prevention measures across households and buildings, especially in cities which are often hotter than rural areas, as well as offering practical advice on how to do that.
Who’s most vulnerable to heat?
Heat can trigger exhaustion and heat stroke, and exacerbate existing medical conditions, including diabetes and cardiovascular, respiratory and cerebrovascular diseases, as well as disrupting sleep and aggravating mental health conditions.
In a fact-sheet, the WHO warned that rising global temperatures, more people living in cities and demographic aging are increasing exposure to heat and vulnerability to its impacts. Some of the most at-risk groups include older people, children, outdoor workers, athletes and sports players, those attending mass public gatherings and poorer social groups, it said.
Employers need plans to protect workers from rising heat stress, UN says
The WHO emphasised, however, that it does not just propose wider use of air-conditioning (AC) as the solution because it is not sustainable, is often unaffordable for those with low incomes and increases energy demand.
“It contributes to both the urban heat island effect and climate change, thus worsening heat exposures in the medium and long term,” the fact-sheet said.
Europe’s intense May heatwave
On Wednesday, Europe’s Copernicus Climate Change Service (C3S) announced that May 2026 was the second warmest May on record globally across land and sea.
Across Europe, the month saw a rapid transition from much cooler-than-average conditions to one of the most intense heatwaves ever observed this early in the year in western Europe, C3S said. Numerous temperature records were broken for May with France, the UK, Ireland and Portugal enduring particularly severe conditions, it added.
C3S noted that the quick flip to a period of extreme heat “likely increased impacts on populations, leaving little time for people – or crops and ecosystems during growing season – to acclimatise to much higher temperatures”.
“Prepare for rougher times”
In a foreword to the new WHO heat plan guidance, Wopke Hoekstra, European Commissioner for Climate, Net Zero and Clean Growth, wrote that extreme heat is responsible for some 95% of all climate-related deaths in Europe, undermines labour productivity and risks overwhelming hospitals.
He noted that investing in emission reductions is far cheaper than paying for climate damage.
“Yet, while we push for emission reductions, we must also prepare for rougher times. Strengthening Europe’s climate resilience, protecting both well-being and economies, is non-negotiable,” he added.
By the end of this year, the European Union plans to adopt a new framework for climate resilience across all sectors, including health.
In the UK, the independent Climate Change Committee warned last month that, in a projected scenario of 2C of global warming by 2050, recent record hot summers will become the “new normal” in the usually temperate country, putting regular stress on domestic agricultural production.
Heatwaves lasting at least a week will be common and could regularly exceed 40C in the south, the committee’s report on adaptation said, posing challenges for keeping vulnerable people sufficiently cool.
It recommended that cooling will be needed in hospitals, prisons, schools and care homes, while regulation should set maximum temperature limits for workplaces.
Berlin’s Heat-Health Action Plan
On Thursday, the WHO said that since the publication of the first edition of its heat and health guidance in 2008, far more scientific evidence and practical experience have been gained. Many countries have since established Heat-Health Action Plans, but their adoption and implementation have been uneven, it said.
Comment: Early warnings for heatwaves can save lives – and we need them now
In Germany, where local authorities are primarily responsible for heat protection, the Berlin Senate adopted a state-wide heat–health action plan in 2025. It contains 72 measures to improve heat protection for residents, including informing them every summer of the risks via traditional and digital media.
A heat protection portal offers access to Berlin’s heat–health action plan, and a map of cool places in the city, as well as behavioural advice.
Berlin Senator Ina Czyborra said the city is also working on the long-term maintenance and expansion of parks, green spaces and water bodies, which can all help alleviate the effects of heat.
“One thing is clear: protection from heat is a cross-cutting task that can only be tackled through a joint effort by all administrative departments and levels, and with the involvement of civil society actors,” she added in a statement.
