Will Climate Change Force Men's Tennis To Shorten Grand Slam Matches?

It was hard to watch the scene unfolding during the first week of the U.S. Open. After winning his first two sets, 22-year-old Jack Sock couldn't move his leg. A trainer ran out to help him sit down near the baseline. The young American--who had been enjoying his best summer on tour--was soon covered in ice bags and cool towels, his tournament over before it really started.

Sock's downfall was later attributed to "heat illness, complicated by cramping." Temperatures hovered around 93 degrees that day. It was even hotter on court, and Sock was playing under the intense midday sun. He's one of 12 men who retired from their matches--four of them for confirmed heat-related reasons--in the first week of the tournament. In the women's draw, there were only two withdrawals, and a lot of the disparity simply comes down to: the women don't play as many sets. They play best-of-three, while the men play best-of-five.

Tennis pundits have long debated whether the men should play best-of-three matches in Grand Slams. The Association of Tennis Professionals—the governing body of men's tennis—already has switched to this format on the ATP World Tour. Proponents of the change argue that marathon five-setters cause more injuries and can cut careers short; that fans no longer have the attention spans for five-hour matches; that best-of-three matches are more competitive and faster paced. Opponents laugh at the suggestion. Wouldn't a three-set format take away the true battles? Doesn't the best-of-five format force players to strategize, to play a smarter game, to come in exceptionally fit?

Roger Federer said last week that there is no excuse for the heat-related retirements. "I mean, it was more on the warmer side, but it's not like impossible, to be quite honest," he said. "I think everybody should be well-prepared. I know we don't play many best-of-five-set matches all the time, so of course the body can react funny once you exceed the two-and-a-half to three-and-a-half hours of play… But I think other players should be so fit that heat really shouldn't matter at that point."

Looking at the year's other Grand Slams, the majority of men are sufficiently prepared. In Melbourne, Paris, and London combined, seven men retired early this year. Heat only becomes an issue when it reaches extremes. For example, the 2014 Australian Open was played during a heat wave and nine men retired early, seven of them in the third set or later. Roland Garros and Wimbledon have not seen nearly as many early retirements, likely because while Paris and London have heat waves, they still don't bring temperatures or humidity to the same levels as in New York and Melbourne.

Twenty years from now, they might.

In an analysis of historic temperatures of the four cities that host the grand slams, researchers at Climate Central found warming trends in every city. They started with the average temperatures in 1968, the start of what is known as the Open Era in pro tennis, when the four-slam calendar become the standard format. Researchers looked at the average daily maximum temperatures during the months when the majors are played: January in Melbourne, Australia; June in Paris, France; July in London, England; and September in Queens, New York.

The data show that Paris is heating up the fastest. Temperatures there have increased an average of 1.26 degrees Fahrenheit each decade. In Melbourne, they're rising .69 degrees per decade; in London, .68 degrees. Queens is actually warming the slowest, at an average of .56 degrees per decade.

Still, the base temperatures for a New York August are already much warmer than those of Paris in June and London in July. Climatologist Andrew Grundstein has also analyzed New York's temperatures and wet globe bulb temperature (a measurement created by the U.S. military in the 1950s, it considers how air temperature, sunlight, wind, and humidity impact human comfort levels). In a 2013 study, Grundstein and colleagues found that by about 2050, there will be an additional 12 days per year in New York where "conditions are so oppressive, that it would be unsafe to participate in athletic activities." The worst conditions are, predictably, from about 11 AM to 5 PM—right when U.S. Open day sessions are played.

So what should tennis do?

Already, January heat in Melbourne is so intense that in 1998 tournament organizers created the Extreme Heat Policy (EHP). It allowed them to stop play if the temperature reached 104 degrees Fahrenheit. They lowered the temperature threshold to 100 degrees for the 2002 tournament, then lowered it again to 95 degrees in 2003. That same year, organizers also began considering the wet bulb globe temperature: high temperatures were not enough of a reason to stop play; wet globe bulb temperature also had to meet a certain threshold. Even if both were met, the decision was ultimately at the referee's discretion.

The policy was first used on January 20, 2003, when temperatures hit 98.6 degrees. It was used again in 2006, 2007, 2009, and 2014—but not necessarily often enough.

"It felt like I was playing in a sauna," Caroline Wozniacki said after a 2014 match, when temperatures reached 108 degrees Fahrenheit. The bottom of her water bottle melted slightly when she put it down on the court. The heat wave lasted four days, spiking at 111 degrees, but the EHP was used only once. Ivan Dodig had it worse than Wozniacki. He cramped during the fourth set of his match, forcing him to retire. "I was thinking I could maybe even die here," he told reporters. More than 950 fans were treated for heat illness; a ball-boy fainted. Organizers said that despite the heat, the humidity was low enough to play on. After criticism from players and fans, the committee clarified the policy for 2015. It moved the EHP threshold back to the original 104 degrees Fahrenheit, but said that play could now be stopped mid-set. Previously, players had had to finish the set.

The Australian Open is currently the only Grand Slam tournament that delays matches due to heat. Grundstein says that it will be very important for New York to implement a similar policy as the weather becomes more hot and humid. One of the risks of climate change is that the extremes will be more extreme. Heat waves will be more intense and more frequent. ATP spokesman Nicola Arzani said that the ATP has a weather policy that, while not specifically related to heat, allows tournament supervisors to delay matches due to extreme weather conditions. This only applies at ATP World Tour events. Each Grand Slam is governed by its own committee, and it's up to those committees to add a heat policy.

Currently, rain is the only weather condition that delays the U.S. Open. In intense heat, they play on—like when temperatures on court reached 111 degrees, in 2010.

The Australian Open grounds also feature three stadiums with retractable roofs, which can be closed to cool down the courts. This rule predates the EHP – it's been allowed since Rod Laver Arena, the first grand-slam venue with a retractable roof, opened in 1988. The U.S. Open is halfway to having one—a roof structure was added to the marquee stadium this year and will be functional next year—but it's for rain. The USTA will not close the roof for heat, according to USTA Managing Director Chris Widmaier.

"When we are conducting long-range assessments about the tournament, we're presently concentrating on the facility itself and future technologies. Climate change has not been amongst considerations as of now," Widmaier told VICE Sports outside Arthur Ashe Stadium on Wednesday night.

All tennis players will feel the effects of playing in a warming climate, but current Grand Slam rules give women more protections from extreme heat. Since 1992, Grand Slam rules have allowed women to take an additional break mid-match when the heat stress index (a measure of air temperature, surface temperature, and humidity) reaches about 86 degrees Fahrenheit. The men are not allowed this extra break, despite having to play more sets.

According to Grundstein, who studies extreme heat's effects on athletic performance, this is another oversight. Grundstein doesn't see climate change forcing the slams to switch to a best-of-three format for men. As long as players adjust the way they train, he said, they should be able to prepare their bodies for hotter conditions—but even when they do so, they're going to need more mid-match breaks in the future.

Teenager Thanasi Kokkinakis could have used one this year. After winning two of the first three sets in his first-round match against No. 12 Richard Gasquet, Kokkinakis started to cramp in the fourth. He served underhand at one point; as he limped out to start the fifth, the chair umpire advised him, "Your health is more important." It was 90 degrees Fahrenheit, with 46-percent humidity. Kokkinakis finally retired after Gasquet (who made it to the quarter-final) built a 2-0 lead. If men played best-of-three, perhaps the outcome would have been different.

If the format for men is going to change, the movement will have to start with the players. ATP spokesman Nicola Arzani said that the notion has not be officially considered. The players council would have to come together and ask for the change. Then the ATP would start the discussion with the relevant governing bodies, he said. As for Grand Slams, USTA's Widmaier said it would have to be agreed upon by all four committees. As of now, there is nothing happening in that regard.

And in the future? If the Earth's climate keeps changing and tennis does not, men's Grand Slams are going to become an extreme sport. So why wait? Sure, a shift would mean the men won't have to withstand the five-set battles that players have faced in every previous decades. Players in previous decades played those contests in lower temperatures and easier conditions. They also used wooden racquets. There is no comparing today's matches to those of the 1970s, 1980s, or 1990s. It's fast becoming a different game, played in a different climate.