World Cup Climate: Impacts and Exposure
The emissions a tournament of this size generates, and the extreme heat it now has to contend with.
The 2026 FIFA Men’s World Cup kicked off June 11 across 16 cities in the United States, Mexico, and Canada. There are 48 teams, 104 matches, and approximately 5 million spectators expected to attend in person. It is the largest World Cup in the tournament’s 96-year history.
It is also, by nearly every measurable metric, the most climatically consequential one, both in terms of impacts the tournament has on climate and the effects of climate on the game. The World Cup is a case study in climate's two-way relationship with global sport: the emissions it generates, and the heat it now has to contend with.
For all of us who care about sport in the outdoors - whether that is running trails, hiking ridgelines, or simply spending time outside - the World Cup is an interesting case study in the intersection of outdoor (large-scale) activity and a warming climate.
What the Numbers Say
The projected greenhouse gas emissions for the 2026 World Cup sit between 7.8 and 9 million metric tons of CO₂ equivalent, depending on the methodology used. That is roughly double the historical average for the four previous tournaments, and significantly higher than the 5.25 million metric tons attributed to Qatar 2022. Scientists for Global Responsibility, which produced one of the most comprehensive analyses to this end, describes the 2026 tournament as the most polluting in football history. Independent carbon accounting by Greenly estimates the total at 7.8 million metric tons, approximately 2.1 times the official figure reported for Qatar 2022.
The structural drivers are well-documented. The three host nations span a continent, placing stadiums at a greater distance away from each other. North America lacks the high-speed rail networks that reduce the carbon cost of travel in Europe or Asia. The tournament also expanded from 32 to 48 teams, adding 16 national squads and 40 matches, and correspondingly greater travel demand across the board.
The figure that most significantly reframes how event emissions should be understood is this: approximately 87 percent of the 2026 World Cup’s projected carbon footprint comes from spectator travel, well above the combined share attributable to stadium construction, team logistics, and operations. International fans, who represent around 35 percent of expected attendance, are projected to generate 74 percent of travel-related emissions. The average overseas visitor will travel nearly 19,400 kilometers on a return journey.
It must be said - many of you who read this substack know that I grapple with my own personal travel (which is still plentiful, both for work but also personally), and I also love welcoming so many visitors to the US (especially given all the beautifully surprising stories that have emerged, too many to link here - go google it - looking at you, Scots in Boston 👀). So I am more laying out the facts here versus offering a condemnation of this kind of travel… all to be discussed, I suppose.
FIFA’s sustainability strategy for 2026 addresses energy efficiency, waste management, and logistics. It does not set a carbon target for the tournament itself, and its stated position on spectator travel is that the organization will “encourage relevant entities to set up efficient air travel routes that reduce distances.” (I’ve talked as well about other large event series’ approach to participant travel, like UTMB.) At COP26 in 2021, FIFA committed to cutting its emissions by 50 percent by 2030 and reaching net zero by 2040 under the UN Sports for Climate Action Framework. In 2023, Switzerland’s advertising regulator ruled that FIFA’s claims of carbon neutrality for Qatar 2022 were unsubstantiated, marking the first formal greenwashing decision issued against a global sports organization.
The Heat Is Already Here
Climate Central analyzed temperature trends at all 16 host sites and found that climate change has increased the number of extremely hot summer days in 14 of the 16 host cities. Miami’s Hard Rock Stadium, where matches are played outdoors, now experiences roughly two additional weeks of extreme June and July heat compared to the 1970s. Researchers at Brunel University found that 14 of 16 host stadiums could exceed the 28°C wet-bulb globe temperature (WBGT*) threshold at which sports medicine organizations and FIFPRO, the global players’ union, recommend delaying or postponing play, with four of those venues potentially reaching 32°C. A separate climate risk assessment, “Pitches in Peril,” produced by Football for Future, Common Goal, and Jupiter Intelligence, reached a similar conclusion using IPCC-aligned modeling: 14 of 16 World Cup stadiums already exceed safe-play thresholds for heat, rainfall, or flooding. The report’s authors suggested this could be the last World Cup played under a traditional summer schedule in North America absent significant adaptation.
*WBGT accounts for humidity, radiant heat, and air movement, capturing the full thermal load on a human body working outdoors, and it differs meaningfully from standard air temperature. Outdoor athletes operating in summer conditions engage with this distinction routinely; as we know, the number on a thermometer reflects only one dimension of heat exposure.
That distinction stopped being theoretical in the tournament’s first week. NPR’s pre-tournament analysis found that more than one in three World Cup matches face dangerously hot, humid conditions, and the early schedule has borne that out. The opening match in Houston - Mexico vs. South Africa on June 11 - drew thousands to the outdoor FIFA Fan Festival, where 90 people were treated for heat-related illness on the first day alone, including 22 cases serious enough to require treatment beyond first aid and four hospital transports. Four days later in Miami, Uruguay’s match against Saudi Arabia took place under an active National Weather Service extreme heat warning, with a heat index exceeding 100°F at kickoff. Miami-Dade Fire Rescue logged 10 heat-related medical calls at the stadium that day, two of which required hospital transport. Houston recorded a separate wave of fan hospitalizations later in the week as temperatures again climbed past 90°F with high humidity.
“I would put all my red flags up for the city of Miami as my biggest place of worry,” said Dr. Douglas Casa, CEO of the Korey Stringer Institute at the University of Connecticut, in comments this week. Casa noted that spectators and event workers face higher heat-illness risk than the athletes themselves, who benefit from cooling protocols, hydration support, and medical staff dedicated specifically to player care (that’s pretty wild to me, but yes absolutely makes sense). Physicians staffing World Cup venues this week described heat exhaustion - including headache, nausea, fatigue, and cramping - as the most common presentation they are treating, and reported stocking IV fluids in anticipation of continued demand as the tournament moves through its hottest weeks.
The exposure extends well beyond ticketed fans inside stadiums and elite athletes on the pitch. Outdoor fan festivals, street watch parties, and the lines and transit waits surrounding every match place large crowds in direct sun for extended periods, often with less shade and fewer medical resources than the stadiums themselves. Researchers at Arizona State University have specifically flagged the risk in queues and transit waits, where shade is scarce and crowd density makes it difficult to leave.
Some host venues offer real protection. Roughly 20 percent of matches are scheduled in air-conditioned stadiums, including Houston, Dallas, and Atlanta. Miami, Kansas City, and Philadelphia remain open-air. FIFA has responded with mandatory three-minute hydration breaks at the 22nd and 67th minutes of every match regardless of conditions, adjusted kickoff times in hotter markets, and an updated water-bottle policy allowing fans into US and Canadian venues with one factory-sealed bottle. These are concrete, in-progress adaptations, and they are also, by definition, responses to conditions that have already arrived rather than preventative measures.
Heat is not the only hazard this week has surfaced. A tropical disturbance moving through the Gulf has brought flash flood risk to Houston, Louisiana, and the broader Gulf Coast during match days this week, with forecasters warning of poor drainage and flooding risk in low-lying areas around outdoor fan festivals, even as the Houston stadium’s retractable roof keeps the matches themselves unaffected. The juxtaposition is instructive: covered stadiums can engineer around extreme heat or rain for the 90 minutes of play, while the outdoor infrastructure surrounding every match, including fan festivals, transit corridors, and parking areas, remains exposed to whatever conditions the week brings.
Additionally, props to Grist for covering FIFA’s lack of wildfire plan or any additional adaptation measures to this end either. But also - damn.
The Outdoor Parallel
For those who spend time in the mountains, on trails, or in open water, the operational challenges the World Cup is navigating are familiar.
Questions about when conditions are safe, how to interpret heat indices, and how to plan around a climate that no longer behaves predictably are central to outdoor event management at every scale. Trail race directors postpone events. Summit attempts are rescheduled to pre-dawn windows. Open-water races are cancelled or shortened. The 2026 Los Angeles Marathon allowed participants to end at mile 18 due to dangerous heat conditions, which I wrote about here. The logic FIFA is applying to stadium management closely mirrors the logic outdoor race directors and land managers have developed, in many cases well ahead of larger governing bodies, over the past decade.
The outdoor community has built practical, distributed climate literacy through direct engagement with changing conditions (whether we know it or not). Heat index interpretation, early-morning start strategies, expanded medical protocols, and real-time weather monitoring are now standard tools in the outdoor event toolkit. That body of operational knowledge applies directly to the World Cup context and to outdoor sports broadly as average temperatures continue to rise.
The World Cup involves outdoor pitches for the majority of its matches, and every fan gathering in an open stadium or street watch party exists in the same thermal environment as anyone recreating outside on the same day in the same city. NOAA has noted that major international events such as the 2026 World Cup can learn directly from the heat management protocols developed by outdoor athletics organizations in prior years.
The Scale Problem
The 2026 World Cup carries the emissions profile it does because FIFA made specific organizational decisions: expanding the tournament from 32 to 48 teams, distributing host venues across three countries on a continent without low-carbon long-distance transport, and declining to set a binding emissions target for the event. These decisions were made against the backdrop of FIFA’s own stated climate commitments.
Dr. Madeleine Orr, assistant professor of sport ecology at the University of Toronto, has described the 2026 World Cup as sending “a dangerous message about the intentions of FIFA and other events to just get bigger and bigger.” The trajectory of projected emissions across future tournaments reinforces this concern. The 2030 World Cup, planned across multiple continents, is projected to generate over 6 million tCO₂e; the 2034 edition, to be hosted by Saudi Arabia, over 8.5 million.
Individual adaptations, including cooling stations, adjusted kickoffs, and carbon offset programs, function at the margins. The decisions that determine the fundamental scale of emissions are structural, encompassing event size, host geography, and transport infrastructure. The adaptations treat the symptoms, but the structural decisions that are what are driving the overall footprint upward.
The counterargument has merit. Global sporting competitions generate civic investment and concentrated public attention at a scale few other events can match. Paris used the 2024 Olympics to update city infrastructure and reserved tickets for local residents to reduce long-distance travel. World Cup host cities have access to the same strategic opportunity: permanent investments in cooling infrastructure, resilient public spaces, and green transit that outlast the 39-day tournament. Whether that opportunity is seized, or whether the primary legacy is carbon expenditure, is a question that will be answered over the next several years.
What to Watch for the Remaining Five Weeks
The 2026 World Cup runs through July 19. One week in, the pattern is already established: heat-related medical incidents at fan festivals and stadiums, an active extreme heat warning during at least one match, and a tropical system testing outdoor infrastructure on the Gulf Coast. Five weeks remain, including several matches still to come in the hottest open-air stadiums on the schedule.
Several questions will define the rest of the tournament. Which venues see additional heat-related incidents as the schedule moves through its warmest weeks? Do the gaps between FIFA’s postponement threshold and FIFPRO’s recommended threshold narrow under continued scrutiny? How do outdoor fan festivals, which have proven more exposed than the stadiums themselves, adapt as the tournament progresses? The data accumulating now will be directly relevant to how the 2030 and 2034 tournaments are planned, and to how outdoor event organizers at every scale approach heat management going forward.
I admittedly have anxiety about this topic. As I wander around London pre-Climate Action Week (see? more travel…) in 28°C trying to find any shade I can (there are more tree covering in wealthier neighborhoods, go figure), I wonder how long we’re going to be able to handle the stress on the body, even in non-athletic endeavors like window shopping and cold brew drinking. Do we seek AC, living more of our lives indoors than we ever have before? What does this mean for outdoor recreation?
For the outdoor community, the first week of the 2026 World Cup offers a documented, large-scale illustration of a challenge that is already reshaping how and when people can safely spend time outside. The sport, the venue, and the institutional scale are certainly different from a trail race or a summit attempt; the underlying climate dynamic is not.