An England fan following their team to every game could generate nearly 3.5 tonnes of CO2, equivalent to heating a UK home for 19 months. BBC Sport analysis reveals the 2026 World Cup expansion to 48 teams and its North American host cities will force fans on some of the longest, most carbon-intensive journeys ever. A supporter flying from London to watch England play every match, including the final in New Jersey, would travel over 14,000 miles. Scotland fans face similar burdens, with potential emissions of 2.8-3.3 tonnes for a run to the final. Climate advocates call the estimates 'deeply disturbing', noting such levels are 'untenable' given climate targets. Fifa acknowledges air travel's significant contribution but highlights initiatives like regional hosting and electric vehicles.