Heat island. Eberwine also hypothesizes a "heat island" effect that could be exerting a subtle force on the baseballs. At the Vet, the fans were farther from the field - 60 feet from home plate to the stands, compared with 49.5 feet at the new ballpark. And the Vet's food concessions were recessed into invisibility; the new park's concessions are plainly visible and well-lighted at night.
Warm air rises because it is less dense than cool air. The proximity of the crowd and the heat generated by the lighted food stands could combine to give a tiny lift to batted balls.
"It's a mini-city in there," Eberwine said.
The big gap. Citizen Bank's wide-open center field might also make a difference. "This could precipitate a wind flow toward the open end," said Charles R. Smith, a mechanical engineering professor at Lehigh University.
These factors were beyond the scope of the RWDI study. With the park still under construction, the engineers used computer models to simulate how the winds alone - unaffected by architecture - would aid or exert a "drag force" on the ball. It did not compare the projected flight paths with those of the Vet.
The study did have one encouraging note for pitchers. When the wind is from the north, it can cut the projected flight path of a ball by 50 feet or more compared to no wind. Unfortunately for the pitchers, north winds are infrequent in summer.
And north winds have their quirks. The computer models found that when winds are blowing briskly from the north, an unexplained uplift undercuts the dampening effect on balls hit to left field.
In fact, on June 13 - the day Thome reflected on that batting practice at the new park three years earlier - a stiff wind was blowing straight in from center. Aaron Rowand, who the Phillies acquired from the White Sox for Thome, hit a drive to left field . . .
. . . and beyond, in a game-sealing grand slam.
Weather or Not |
More about wind and baseball:
Contact Anthony R. Wood at 610-313-8210 or at twood@phillynews.com.
