The FIFA World Cup knockout stage promises high-stakes football, but some of its biggest fixtures will also test endurance. With matches scheduled in Miami, Toronto and Philadelphia under intense heat, players and fans are preparing for conditions that could influence everything from match tempo and recovery to health and safety.

A new analysis by Climate Central warns that the ongoing heatwave affecting parts of North America has been made significantly more likely by climate change. Several knockout fixtures, including Argentina vs Cape Verde in Miami, Portugal vs Croatia in Toronto and Paraguay vs France in Philadelphia, are expected to be played in temperatures above 35°C. Scientists estimate these conditions are at least five times more likely because of climate change, with Miami facing a tenfold increase in likelihood.

The Tournament Has Already Felt the Heat

Extreme weather has already left its mark on the World Cup. During the group stage, at least two matches were played in conditions exceeding the Wet Bulb Globe Temperature (WBGT) threshold at which the global players’ union, FIFPRO, recommends delaying or postponing play. The France-Iraq fixture was also delayed by two hours because of storms, marking the first weather-related World Cup delay since 1974.

The report further found that 25 World Cup matches were played on days when climate change increased the likelihood of high wet-bulb temperatures, highlighting how extreme weather has become a recurring feature of the tournament.

FIFA World Cup: When Heat Changes Football

Football depends on constant movement. Modern teams rely on relentless pressing, rapid transitions and repeated bursts of sprinting over 90 minutes. But as temperatures rise, sustaining that intensity becomes increasingly difficult.

“The biggest mistake people make is focusing on the air temperature. That number is measured in the shade, whereas elite footballers compete under direct sunlight while generating large amounts of body heat through intense physical activity,” said Professor Ollie Jay, Professor of Heat and Health and Director of the Heat and Health Research Centre at the University of Sydney.

Players rely on the evaporation of sweat to stay cool during intense matches. In hot, humid conditions, that cooling process becomes less effective, placing them under far greater physiological strain than air temperature alone suggests, he explained.

Jay said much of the discussion around the tournament had centred on altitude in Mexico City, but warned that the combination of heat and humidity in venues such as Philadelphia could have an even greater impact on performance.

Sports scientists use Wet Bulb Globe Temperature (WBGT), which combines heat, humidity, sunlight and wind, to assess heat stress during physical activity. Jay cautioned against relying on the Heat Index, saying it was never designed to assess elite athletes competing at maximum intensity in direct sunlight.

As matches wear on, the effects become increasingly visible. Players sprint less frequently, recover more slowly after losing possession and conserve energy instead of pressing aggressively. Coaches may respond by slowing the tempo, making earlier substitutions or adjusting tactics to manage fatigue. In knockout football, where a single mistake can decide a match, even small declines in physical or mental performance can influence the outcome.

Can Heat Create an Unfair Advantage?

The weather may also influence the tournament beyond individual matches.

Climate Central notes that knockout fixtures in Miami, Philadelphia, Toronto and New Jersey are being played in stadiums without air conditioning, exposing players to greater heat stress than those competing in climate-controlled venues in Houston, Dallas and Atlanta.

Teams advancing from hotter venues could carry more fatigue into later rounds than opponents playing under cooler conditions. While every team follows the same tournament schedule, the physical demands of each match vary depending on where it is played, raising questions about whether rising temperatures are creating an uneven playing field.

Fans Facing the Challenge

While cooling stations and revised water policies inside stadiums offer some relief, many supporters spend hours walking to venues, standing in security queues and gathering at fan zones under direct sunlight.

According to the report, more than 100 spectators required treatment for heat-related illnesses during the tournament in Houston, while fan festivals in Toronto, Houston and Atlanta were disrupted or cancelled because of extreme weather.

A Challenge Football Cannot Ignore

Extreme heat is forcing football to rethink how tournaments are staged.

While FIFPRO recommends postponing matches when the Wet Bulb Globe Temperature exceeds 28°C, FIFA’s competition protocols use a higher intervention threshold of 32°C. As a result, no matches have been rescheduled because of heat alone, although mandatory three-minute hydration breaks have been introduced midway through each half.

As tournaments are increasingly held under hotter conditions, football’s governing bodies may have to look beyond hydration breaks. Scheduling, kickoff times, stadium design and player welfare protocols are likely to become as important to the future of the game as tactics on the pitch.

Humid Heat in India is emerging as a growing public health threat. Through data, expert insights and lived experiences from across the country, EdPublica explores how rising heat and humidity are making everyday life increasingly difficult for millions of Indians.

By 9 a.m., Radha, a 55-year-old office worker from Kottayam in the southern Indian state of Kerala, is already drenched in sweat as she waits for her bus. By noon, waves of heat, anxiety and discomfort begin to set in. Menopause had already brought frequent hot flashes, she says, but rising temperatures and humidity have made them harder to endure.

For Radha, relief no longer comes easily. Even routine tasks feel more exhausting than they once did. Her experience reflects a growing reality across India and much of the world: climate change is not only making the planet hotter, it is making heat harder for the human body to bear.

Humid Heat in India Taking a Growing Toll

When high temperatures combine with high humidity, the body struggles to cool itself through sweating, its primary cooling mechanism. As moisture in the air increases, sweat evaporates less efficiently, causing heat to build up inside the body.

A recent analysis by Climate Central found that dangerous humid heat days have more than doubled globally since the 1970s. The average number of dangerous humid heat days has risen from around 10 days per year to 23 days annually.

Alarmingly, climate change is now responsible for nearly two-thirds of these dangerous humid heat days. The consequences are increasingly visible. A study examining mortality linked to extreme heat events since 2000 estimates that more than 260,000 people have died from heat-related hazards worldwide.

Globally, climate change is now responsible for six times as many dangerous humid heat days each year as it was in the 1970s, underscoring how rapidly the risk has intensified. In 2025 alone, the world experienced an average of 23 dangerous humid heat days. Climate Central estimates that 19 of those days, or 83 percent, were added by human-caused climate change.

“These findings show how profoundly climate change is reshaping our world,” said Kaitlyn Trudeau, Applied Climate Scientist at Climate Central. “Dangerous humid heat has gone from being an uncommon event to a defining feature of daily life in some regions, pushing conditions closer to the limits of what the human body can safely endure.” Climate Central’s analysis of 961 cities worldwide found that 69 percent, or 665 cities, are now experiencing significantly more dangerous humid heat days because of climate change. On average, these cities recorded 46 additional dangerous humid heat days each year during the last decade compared with a world without human-caused warming.

Researchers say the findings highlight how climate change is evolving from an environmental concern into a growing public health emergency, particularly in regions already struggling with heat exposure, limited access to cooling and inadequate health infrastructure.

What Is Humid Heat?

Scientists often use “wet-bulb temperature” to measure humid heat. The metric combines air temperature and humidity to estimate how effectively the human body can cool itself through sweating.

Climate Central defines wet-bulb temperatures of 25°C or higher as dangerous humid heat conditions. When humidity and temperature combine to push wet-bulb temperatures upward, the body’s natural cooling system becomes less effective.

In extreme conditions, the body can no longer regulate its temperature adequately, increasing the risk of heat exhaustion, heat stroke and even death.

Older adults, children, pregnant women and people with pre-existing health conditions face the greatest risks. High humidity can worsen cardiovascular stress, respiratory illnesses and other heat-related health complications.

“Dangerous humid heat has more than doubled since the 1970s. We’re already seeing the consequences play out in real time,” said Lisa Patel, Clinical Associate Professor of Pediatrics at Stanford Children’s Health and Executive Director of the Medical Society Consortium on Climate and Health.

“As a pediatrician, these numbers are a wake-up call. This kind of data is exactly the tool clinicians and public health officials need to anticipate where heat-related illness will strike and who is most at risk before people end up in the emergency room.”

How Humid Heat Is Affecting India

Humid Heat in India is already becoming visible in several cities, particularly along the country’s southern and eastern coasts.

According to Climate Central’s analysis, Tamil Nadu emerges as India’s most affected state. Tirunelveli experiences an average of 273 dangerous humid heat days annually, the highest among Indian cities. Chennai follows with 257 days, while Tiruchirappalli records 251. Vijayawada and Visakhapatnam in Andhra Pradesh, along with Kolkata and Mumbai, are also among India’s humid-heat hotspots.

The danger does not end when people move indoors.

A separate study by Climate Trends found that heat exposure frequently continues inside homes. Researchers monitored temperatures and humidity in 50 low- and middle-income households in Chennai between October 2025 and April 2026 and found that indoor temperatures regularly exceeded 32°C.

Some households experienced more than 5,700 hours above this threshold—equivalent to nearly eight months of continuous heat exposure. Most households recorded between 3,000 and 5,000 hours of such conditions.

The findings suggest that for many urban residents, especially those without access to air conditioning, relief from heat remains elusive even indoors.

Heat, Menopause and Everyday Life

For women such as Radha, humid heat can intensify already challenging health conditions.

The World Health Organization notes that hot flushes and night sweats are among the most common symptoms associated with menopause. These episodes involve sudden sensations of heat in the face, neck and chest, often accompanied by sweating, flushing, palpitations and discomfort.

Women who have undergone hysterectomy are known to experience more frequent and severe hot flushes. According to NFHS-5 data, nearly one in ten women aged 30 to 49 in some regions of India have undergone the procedure.

As temperatures and humidity rise, these symptoms can become even more difficult to manage, adding another layer to the health impacts of climate change that often goes overlooked.

A City Struggling to Cool Down

In Mumbai, 59-year-old driver Vikas says heat has become one of the city’s biggest challenges.

Water shortages are becoming more common, and even routine outdoor work is growing increasingly difficult.

“Sometimes people go to the beach at night just to find some relief from the heat. Even a brief spell of rain feels like a blessing now,” he says. “The problem is only going to get worse.”

His observations echo broader climate trends in the Mumbai Metropolitan Region. Climate Central’s analysis shows that Mumbai experiences an average of 206 dangerous humid heat days annually, while nearby Dombivli and Thane record even higher numbers. The conditions he describes are reflected in current forecasts. Climate Central projected a daily high wet-bulb temperature of 25.6°C in Mumbai on June 23, a level considered dangerous humid heat.

Surfing Through a Hotter Coastline

Further south, the effects are also being felt along India’s coast.

Rajaguru, a surfing instructor in Puducherry, says summers are arriving earlier than before, often beginning in February instead of March.

“We go surfing early in the morning, but even then the heat feels much more intense than it used to,” he says. “Sunburns and skin rashes are becoming common. Summer arrives with extreme heat, while the monsoon season increasingly brings cyclones.”

He has also noticed rising sea temperatures and changes in water conditions that affect both tourism and outdoor activities.

For people whose livelihoods depend on spending long hours outdoors, humid heat is becoming more than an inconvenience—it is becoming an occupational hazard.

The Vulnerability Gap

These experiences reflect a larger challenge facing India. The impacts of Humid Heat in India are magnified by inequalities in access to cooling, housing and reliable electricity.

Between 1995 and 2024, the country experienced 430 extreme weather events, resulting in more than 80,000 deaths and economic losses exceeding USD 170 billion. Rapid urbanisation has intensified the urban heat island effect, making cities significantly hotter than surrounding rural areas.

The latest Climate Change in the Indian Mind survey found that 84 percent of Indians report experiencing the effects of global warming. Yet only 15 percent of households own an air conditioner and 27 percent have access to an air cooler.

Even for those with cooling systems, reliable electricity is not guaranteed. Around 66 percent of Indians experience power disruptions on a typical day, even as demand surges during heatwaves. On May 21, 2026, India’s peak electricity consumption reached a record 270 gigawatts.

Despite being the world’s third-largest emitter of carbon dioxide, India’s per-capita emissions remain relatively low, reflecting deep inequalities in energy consumption and access.

For millions of people, escaping extreme heat is simply not an option.

When the Air Stops Offering Relief

Dangerous Humid Heat in India is already reshaping how people live, work and survive. As temperatures and humidity continue to rise, the boundary between uncomfortable and life-threatening conditions is becoming increasingly thin.

For millions of Indians, the challenge is no longer adapting to hotter days. It is adapting to air that no longer offers relief. As humidity rises alongside temperatures, surviving heat may become as much about access to cooling and electricity as it is about climate itself.

The future of climate adaptation may begin not in policy documents or air-conditioned offices, but in homes, buses, streets and workplaces where the heat is already impossible to ignore.

Pollution in India has embedded itself into everyday life. The extent to which it affects people often goes unnoticed until it rides along with morning traffic, seeps through open windows, and settles into daily routines. Cities like Delhi and Ghaziabad routinely appear in global pollution rankings. The problem is structural, persistent, and increasingly demand climate action.

A recent survey on public perceptions of environmental issues suggests that Indians view climate change as an immediate threat to their local communities and personal well-being.

Widespread Concern Over Pollution

The survey highlighted a high level of anxiety regarding pollution in India. Around 77% of Indians expressed significant concern about air pollution. This concern exists alongside fears of other climate-related hazards, including severe heat waves (77%) and droughts or water shortages (76%). The findings suggest that the public views pollution as part of a broader environmental crisis already affecting everyday life.

“People need credible information about what governments, businesses, communities, and households can do, how clean-energy transitions create jobs and improve air quality, and how local actions connect to larger climate goals,” Jagadish Thaker, one of the lead authors of the study, told EdPublica.

Public concern over air quality is also reflected in environmental data. India ranked sixth among 143 countries in PM2.5 pollution levels in the 2025 World Air Quality Report. At the city level, the situation appears even more severe, with New Delhi continuing to rank as the world’s most polluted capital city for the eighth consecutive year.

Identifying the Culprits: Fossil Fuels and Coal

“What is striking in our data is how consistently supportive Indians are of the energy transition. These findings suggest that public opinion may be less of a barrier to climate and energy policy than is often assumed. For communicators, one challenge is helping people understand how long-term energy transitions actually occur and what role citizens can play in them,” said Thaker.

Large majorities of respondents identified oil (76%) and coal (68%) as polluting sources of electricity. India’s energy sector still relies on coal for nearly 70% of its electricity generation. At the same time, there is growing public recognition that coal is a major contributor to both local air pollution and global warming.

Interestingly, around 82% of Indians support banning the construction of new coal-fired power plants and gradually shutting down existing ones in favour of solar and wind energy. This support is driven by the belief that such a transition would benefit the people of India (87%) and offer the best pathway toward a “healthy, safe, and prosperous future.”

Shift Toward Climate Action

Support for renewable energy transitions is particularly strong. Nearly 95% of respondents favoured a national programme prioritising renewable-energy job training for youth and women, while 93% supported renewable-energy job training in general.

At the same time, 78% of Indians believe the government should be doing more to address climate and pollution-related challenges. Respondents also pointed to the need for hyperlocal, area-specific training programmes and structural policy reforms.

Reflecting on the findings, Thaker said: “These findings suggest that climate communication should not focus only on risks. Indians appear highly interested in solutions, skills, and opportunities. Effective climate education can help people understand climate change, but it can also help them see pathways to participate in the transition through employment, innovation, and community action. Education is most powerful when it links climate action to everyday benefits and opportunities.”