The upcoming 2026 FIFA World Cup, co-hosted by the United States, Mexico, and Canada, faces a heightened risk of games being played in unsafe temperatures due to human-induced climate change, according to a report by researchers at Imperial College London. This increased heat poses a significant challenge to player safety and the quality of the tournament.
Rising Temperatures and Unsafe Conditions
Estimates suggest that five games could be played in unsafe heat conditions during the 2026 tournament, an increase from the three games estimated for the 1994 World Cup, the last time the event was held in the U.S. Researchers used a threshold of 28°C (83°F) wet bulb globe temperature (WBGT) for unsafe conditions, a standard recommended by FIFPRO, the international players' union. WBGT accounts for temperature, humidity, sun, and wind to measure the stress on the human body. FIFA currently considers postponing matches only at levels exceeding 32°C (90°F).
Friederike Otto, a professor of climate science at Imperial College London and a co-author of the report, stated that the heightened risk demonstrates climate change's tangible impact on the viability of holding major sporting events during the Northern Hemisphere summer. The final match, scheduled for July 19 at MetLife Stadium in New Jersey, has a 3% chance of reaching the 28°C (83°F) threshold for postponement.
Nearly a quarter of all World Cup games are projected to be played in temperatures above 26°C (79°F), with approximately five matches expected to exceed 28°C (83°F), nearly double the number from 1994.
Player Welfare and Performance
Sixty current and former professional soccer players have signed an open letter urging FIFA to update its heat guidelines. They highlighted that extreme heat can lead to lightheadedness, dizziness, fatigue, and muscle cramps, reducing players' ability to perform with intensity. "You can run less and it becomes impossible to play with the same intensity as with more average temperatures," the letter stated.
Douglas Casa, CEO of the Korey Stringer Institute, explained the physiological impact of heat on athletes. Under severe heat and dehydration, heart rates rise, muscles fatigue faster, and the body's cooling mechanisms are strained. Extreme conditions can lead to a point of "volitional exhaustion," where athletes voluntarily stop due to inability to continue. While today's athletes may be more prepared for heat due to advancements in training and equipment, retired player Sávio Bortolini Pimentel noted that even trained athletes feel the heat dramatically, which can automatically reduce the pace of play.
Proposed Solutions and FIFA's Stance
In addition to urging updated heat guidelines, the players have also called on FIFA to address the climate crisis by dropping fossil fuel sponsors and adjusting schedules to reduce travel. To mitigate risks during games, experts suggest implementing aggressive cooling strategies in locker rooms and extending hydration breaks. Casa recommended extending breaks from three minutes to six, and emphasized the importance of rapid cooling methods like cold towels or plunges for players entering locker rooms with body temperatures potentially reaching 40°C (104°F).
Casa suggested that proactive cooling measures could ensure fans receive the highest quality game possible, given the significant cost of tickets. For spectators, he recommended that FIFA allow free water-filling stations inside stadiums, as fans can also suffer from heat-related illnesses. However, FIFA's stadium code of conduct currently prohibits fans from bringing empty refillable containers.
The 2022 World Cup in Qatar was moved to winter due to extreme heat, and a recent Club World Cup in the U.S. saw no postponements despite temperatures exceeding 32°C (90°F), though the new report suggests higher risks for the 2026 tournament.
FIFA has not yet announced any changes to its heat guidelines or scheduling protocols in response to the report and the players' concerns.