Rising temperatures are casting a shadow over the World Cup, with a new study by World Weather Attribution warning that 25% of tournament matches are likely to be played in conditions above 26C. Researchers said the finding points to serious dangers for both players and supporters at the event, which will be staged across North America in the US, Canada and Mexico during June and July. The Wet Bulb Globe Temperature (WBGT) measures the level of physical heat stress placed on the human body. Experts broadly regard a WBGT of…