News•January 21, 2015

Heat Stroke, Anyone? Tennis Grand Slams Heating Up

The hottest grand slam event on tennis’ calendar began this week under mercifully mild skies. Temperatures at the Australian Open have kept to double digits so far, contrasting with the brutal heat waves that struck last year, causing players and ball kids to pass out. Those heat waves have since been categorically linked by multiple teams of scientists to the buildup of greenhouse gas pollution in the atmosphere.

Maria Sharapova in Melbourne in 2014.
Credit: Michael Brown/Flickr

And new research by Climate Central has shown how climate change is affecting professional tennis — not just in Melbourne, but the world over, with all four grand slams getting hotter.

“It's inhumane,” Canadian tennis player Frank Dancevic told reporters after collapsing in last year’s scorching conditions. The mercury regularly neared or touched 110°F in Melbourne on multiple days during the 2014 tournament, with courtside conditions far hotter, sickening athletes and causing at least one water bottle to start melting into the artificial playing surface. “Passing out with heat-stroke is not normal.”

Tennis isn’t the only sport being affected as temperatures rise, the cryosphere melts and other atmospheric conditions change as greenhouse gas levels rise. The Iditarod in Alaska is running low on snow. The National Hockey League is worried about the future of outdoor rinks, which are critical training grounds for young players. Spring practices are becoming more brutal for football players in warmer climates as temperatures rise. Climbing Mount Everest is becoming more treacherous as mountain-stabilizing ice melts away. The number of cities that could host the Winter Olympic Games is forecast to decline. And the atmospheric changes driven by global warming could be giving sluggers an upper hand over pitchers.

Climate Central analyzed temperatures for all four cities that host grand slam tournaments, and the average daily maximums were analyzed for the months when the bulk of the matches are played for each tournament. Since 1968, when professionals began competing in tennis’ grand slams, temperatures in the four host cities have been getting noticeably hotter.

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The Australian Open is the hottest of the grand slam events — temperatures in Melbourne in January can vary wildly, with average maximums typically in the high 70s. But the analysis shows maximum temperatures are rising fastest at the French Open, which is played in Paris.

The Climate Central analysis shows that January daily high temperatures in Melbourne have risen at a rate of 0.69°F per decade since 1968. In Paris, the rise has averaged 1.26°F per decade during the same period. In Queens, the New York borough that’s home to the U.S. Open, the rise has been 0.56°F per decade during September. London, which hosts Wimbledon, has seen an average rise of 0.68°F per decade in July since 1968.

A fan cools off in front of some fans at the Australian Open in 2014.
Credit: Ameel Khan/Flickr

When it comes to Melbourne’s January weather, “there’s substantial natural variability between different years,” David Karoly, a meteorology professor at the University of Melbourne, said. “But there’s also a clear warming trend of more than 1°C (1.8°F) over the last 100 years in Melbourne. That’s consistent with the warming across the whole country, which has been strongly attributed to human influences on climate.”

Organizers of the Australian Open were seemingly indifferent last year to the growing heat challenges created for millionaire professional players by Melbourne’s often scorching Januaries. “No one is saying it is terribly comfortable to play out there,” the tournament’s chief medical officer said last year after Britain's Jamie Murray was treated for heatstroke, BBC reported. “But, from a medical perspective, we know that man is well adapted to exercising in the heat. Whether it is humane or not is a whole other issue.”

That’s not to say that organizers weren’t paying attention, though. If Melbourne’s temperatures hit triple digits during Australian Open play, tournament referees will draw on new guidance in deciding whether to suspend play following new tweaks to the Australian Open’s heat policy. Referees have been directed to consider weather forecasts and the state of play in a game before halting or delaying play — but not before the temperature exceeds 104°F, as was the case regularly last year, and not before the wet bulb globe temperature tops 90.5°F.

(Wet bulb globe temperature considers temperature, wind speed, humidity and sunlight intensity. The metric was developed by the U.S. military in the 1950s to protect recruits and is now a common measurement used by occupational health and athletics officials.)

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“The [heat] policy has not changed as such,” tournament spokesman Prue Ryan said. “By providing an actual temperature and reading there’s now greater clarity on when the policy may be activated, and implementation is always at the referee’s discretion.”

Ryan said the Australian Open is the only grand slam played with a heat policy, and that it’s the only event featuring three retractable-roof stadiums that can be closed in extreme weather — be it rain or heat.

University of Georgia geography professor Andrew Grundstein, an expert in climate and health, doesn’t think climate change poses an immediate threat to the tradition of playing the Australian Open in Melbourne in January. “People can acclimatize to the heat,” he said. “They could make sure players had plenty of fluids and appropriate rest breaks between sets, depending on conditions, and medical staff monitoring players for signs of heat injuries.”