The warming climate is forcing marathons to consider changes to keep runners cool

Paul Grinvalds has completed 114 marathons in all 50 states, but he still wilts when he races in temperatures beyond 60 degrees Fahrenheit (15.5 Celsius). “One thing about marathoners is typically we're kind of stubborn,” said Grinvalds, 68, from West Des Moines, Iowa, who finds even temperatures in the 50s F (10 C) a bit warm. Such an experience can also be dangerous, a reality that marathon organizers are having to confront as climate change, caused mostly by the burning of fuels like coa...

By SCOTT McFETRIDGE