Jeering and heckling are increasingly commonplace, even at grand slams, as spectators try to influence matches

Midway through the first week of the US Open a couple of years ago, Jiri Lehecka’s attempts to find his form were disrupted by incessant taunting from a spectator close by. “There was a guy who sat just behind my bench on a smaller court, court four, and he was talking to me basically for the first three sets, like non-stop,” Lehecka says. “He was talking to me like: ‘You can’t do it. You are tired. He’s better than you are.’”

Lehecka maintained his composure and closed out the match, but even as he focused on navigating the intense stress of competition, he believed he understood this spectator’s motivations. The spectator, he thinks, was not there just to cheer for his favourite player: he was a bettor who had put money on Lehecka to lose. He had entered court four solely to influence the outcome of the match.

Climate experts warn that US Kalshi and Polymarket users are ‘gamifying disasters’ as they bet on events like heatwaves and daily temperatures

Online prediction markets, saturated by money staked on sport, crypto and politics, have now set their sights on a promising new area of growth: betting on the future livability of the planet itself.

The rise of gamified predictions on the unfolding climate crisis, and shorter-term weather forecasts, has been underscored by a new deal that allows Kalshi, a leading online financial exchange, to access data from the Weather Company, owner of the Weather Channel, to verify weather-related betting outcomes.