Climate change is making major league baseball hitters more fearsome than ever by allowing them to hit 50 more home runs each year, a study released last week calculates.
Warmer, less dense air that allows the ball to travel further makes a modest contribution to the jump in the number of home runs hit since 2010, according to a statistical analyst published in the Bulletin of the American Meteorological Society by Dartmouth College researchers.
They analyzed more than 100,000 Major League Baseball games and more than 200,000 slapped balls in play over the past few years, in addition to factoring in factors like weather and stadiums.
“Climate change is giving major league baseball more juice,” summed up the study’s author, climatologist Justin Mankin.
It’s a simple matter of physics.
When the air heats up, the molecules move faster and away from each other, making the air less dense. The hit balls therefore travel farther, since the thinner air offers less resistance to slow them down. A few more yards, or even a few centimeters, can mean the difference between a home run and a fly ball, said Alan Nathan, a University of Illinois physicist who was not involved in the study.
Dr. Nathan is one of a group of researchers recruited by Major League Baseball to study the rise in home runs. His own calculations arrive at the same results as those of the Dartmouth experts.
Both Norman and the Dartmouth researchers found that each degree Celsius increase in air temperature added 1.8% to the probability of a home run. Home runs fueled by global warming account for 1% of all home runs slammed in a season, according to the Dartmouth study.
Non-climatic factors, however, contribute more to the bombardment that pitchers experience, according to researchers and baseball experts. The biggest factor would be the ball and the size of the seams, Norman said, and Major League Baseball made small changes to make the ball more inert before the start of the 2021 season.
Other factors include the attention batters pay to the angle at which they return the ball; stronger hitters; and throws that arrive faster.
The study began after the inglorious era of steroids in major league baseball ended, which saw a few records fall.
Former Major League Baseball players and executives say the study matches their own on-field observations.
“We’ve thought that for a number of years,” said Philadelphia Phillies president of baseball operations Dave Dombrowski, who was once general manager of the Montreal Expos. When it’s hotter the ball travels more and they have scientific evidence to back it up. »
Home runs have always fluctuated depending on the stadium, due to such simple factors as the varying distance from home plate to the fence or even wind conditions.
The Dartmouth researchers found that the impact of weather on home runs also varies by terrain. Wrigley Field in Chicago still hosts several games in broad daylight, and it’s where global warming makes it easier to hit home runs the most. Statistical analysis found no such effect at Tropicana Field in Tampa Bay, the only permanently indoor stadium in major league baseball.
“It’s interesting to think about that,” said former pitcher David Cone, who once played in five All-Star games and now works as a television analyst. I might be a bit more interested in how the ball is made, variables and specs. But the weather is important, that’s for sure. »
The heat is also difficult for players and fans to bear. The average temperature in June, July and August in the United States has increased by more than 2 degrees Celsius over the past 40 years, according to the United States National Oceanic and Atmospheric Administration.
And that’s just the beginning. Dartmouth researchers have calculated that global warming has allowed about 500 more balls to fall over the fence since 2010, but thousands more could do the same over the next few years.
The exact number of additional home runs will depend on the heat, which will depend on the amount of greenhouse gases released into the atmosphere, which will depend among other things on the total consumption of hydrocarbons.
Mr. Callahan performed various computer simulations.
Under the worst-case warming scenario—which the planet appears to be on its way out of, according to the most recent emissions—there would be 192 more home runs per year by 2050 and 467 by 2100. But a pollution scenario more modest, more like the current situation, predicts 155 more circuits by 2050 and about 255 more by the end of the century, according to Callahan.
Baseball generates so much analysis and statistics that it becomes easier to detect the impact of climate change, Mankin said. Despite this, it is not possible for the researchers to say that such a circuit would have remained within the limits of the field without global warming.
Several climatologists told The Associated Press that the study makes perfect sense and that the numbers were well analyzed, while also pointing out that factors other than climate probably have a greater impact.
Andrew Dessler of Texas A University
“Climate change will reshape many of the things we love in subtle and pernicious ways,” he said. Attending fewer outdoor baseball games won’t bring civilization down, but it’s another demonstration of how our lives will change due to greenhouse gas emissions. »
