NEW YORK, June 10 -- The biggest World Cup ever staged kicks off Thursday night at the Azteca in Mexico City, and before a single ball is struck the tournament has already locked in one record its organizers would rather not discuss. No edition of this competition has ever carried a heavier climate bill, and none has tried harder not to count it.

The bill has a number now. Greenly, a carbon accounting platform that built a bottom-up estimate covering team flights, fan travel, stadium operations, accommodation and waste, puts the tournament's footprint at 7.8 million metric tons of carbon dioxide. That is more than double the 3.8 million tons reported for Qatar 2022, roughly the annual exhaust of 1.7 million cars. Greenly's analysts are c...