The Red Sox are hoping to have hot bats Wednesday night, but the air temperature at Fenway Park could play a small role in whether a sharply smacked ball only makes it to the warning track or sails into...
The Red Sox are hoping to have hot bats Wednesday night, but the air temperature at Fenway Park could play a small role in whether a sharply smacked ball only makes it to the warning track or sails into the stands for a home run.
As of Tuesday afternoon, the National Weather Service was predicting a unseasonably cold first-pitch temperature of 49 degrees, with a five-degree drop by the end of the game.
The biggest effect of the temperature will be on the players themselves as they try to stay warm and loose, said Patrick Drane, assistant director of the Baseball Research Center at UMass Lowell.
But when it comes to the physics of the game, the cold will make it a bit harder to hit a homer, because breaking balls curve a bit more and because denser, colder air creates more air resistance, giving a fly ball less distance.
“If a ball comes off the bat at about 100 miles per hour at a 25- to 30-degree launch angle, if the temperature is 70 degrees that ball is going to carry about 400 feet,” said Alan Nathan, professor emeritus of physics of the University of Illinois at Urbana-Champaign.
“But for each change in temperature of 10 degrees, you change the distance by about 2 1/2feet,” he said. “It’s not a big effect. But if you compare a 40-degree game to a 90-degree game, that’s 12 1/2 feet. That’s going to be enough to make the difference between a warning-track fly ball and a home run.”
Colder, denser air also affects breaking balls, providing more friction against the raised seams. “Other things being equal, there will be more break to the pitch in cold weather than warm weather,” said Nathan, the man behind The Physics of Baseball website. “If the game were played in a vacuum, there wouldn’t be any breaking balls at all.”
And what about the temperature effect on the bats and balls themselves?
Nathan said cold wooden bats hit the same as warm ones. Whether chillier baseballs are harder to hit for distance is a matter for debate.
Nathan said his research years ago suggested that a fly ball will fall 10 feet shorter if the ball’s temperature is 35 degrees instead of 70 degrees. “It’s as big as the aerodynamic effect.”
Drane isn’t so certain, even though some of his research has suggested exactly such an effect.
About a decade ago, he and colleague James Sherwood tested the bounciness of NCAA baseballs fired against a wall.
At 60 mph, temperature had a significant effect. Baseballs kept in the freezer were 2 percent less bouncy than those warmed in a toaster oven to 120 degrees.
But when the impact speed was increased to 100 mph, the effect disappeared. Only the coldest baseballs lost some of their bounciness.
“You have a 90-mile-per-hour pitch but you have a batter swinging at 40, 60, 80 miles per hour depending on where you’re hitting. So you’re talking 90- to potentially 180-mile-per-hour velocities,” said Drane.
“The temperature of the ball is not coming into play,” he said. “Things like the wind will have a much bigger effect. Things like air density can have a much bigger effect.”