After a big one By mistake on his first run, Daniel Yule assumed he was out of the men’s slalom at this season’s Alpine Ski World Cup. “I had already packed my bag, and I was ready to go back to the hotel,” he said In a TV interview after last weekend’s event in Chamonix, France.

Instead, his time was good enough to advance to the second round. From there, in last place, the Swiss skier won the entire event. Never before in the competition’s 58 years has anyone risen from such a low position to claim the trophy in a single run. It was a testament to Yule’s skiing — but also to the inescapable reality of climate change.

gave Temperature that day Chamonix had risen to an unusual 12 degrees Celsius (54 degrees Fahrenheit) – well above the average maximum in February -1. Competition rules dictate that slalom skiers perform their second run after the first in reverse order of rank—meaning Yule, in last place, will go first on the second run on an unbroken piste. His competitors would be running under the midday sun on a fast-melting slope, carved by those before them, and the winner would be the one with the shortest cumulative time over their two runs. “I was definitely lucky,” Yule said.

Slalom skiing requires competitors to navigate their way around a series of gates as they descend. The turn, therefore, is a race-determining factor. When skiers perform for the first time, like Yule in his second run, they are able to choose where they turn around each gate. As they do this, the pressure of their skis creates wrinkles in the snow. Anyone who follows is then, to some extent, forced into these conflicts, and as they deepen, it becomes harder for those who follow to follow these lines. Which suits their own style.

Arnaud de Mondinard, head of alpine ski research at snow sports equipment brand Salomon, says this routing effect is more pronounced and even faster on warmer days. On top of that, as the snow melts on the run, it becomes slushy, making it more difficult for skiers to traverse. And, de Mondenard is keen to highlight that the ice doesn’t melt or compress evenly across the course. For the latter skiers, assessing the stability and texture of the terrain would have been a significant challenge.

On such a gentle slope in Chamonix, these are all factors that would have contributed to the skiers’ performance. “It was really hard at the end. It was really, really messy,” said Clement Noel, the French athlete who dropped from first place to third, finishing more than 2 seconds slower than Yule in the second run. By the time Noel started his second run, the sun had been melting the piste more than 45 minutes since Yule had started.

Some have cited Yule’s performance as one of the first examples of climate change disrupting professional sports outcomes. Mark Maslin, Professor of Earth System Science at University College London and author How to save our planetI have written A post on LinkedIn: “Credit where credit is due to Yule, and congratulations to him … but no one can deny what happened here … the reason was painfully obvious.”