4 ms·

Something I rarely hear discussed around the MLB home run boom, maybe because it's just too obvious (?): Warm weather -> less dense air -> balls fly farther. R

Something I rarely hear discussed around the MLB home run boom, maybe because it's just too obvious (?): Warm weather -> less dense air -> balls fly farther. Recent years have been record warm. Does that have any measurable or meaningful effect?

ofcrpls 9y ago
Similar discussion on cricket ball and how science shows no impact of weather on balls flying through air significantly enough but still remains a common misconception through out the sport's fraternity. http://theconversation.com/why-we-think-the-weather-affects-how-a-cricket-ball-swings-when-it-doesnt-46587 http://theconversation.com/why-we-think-the-weather-affects-...
stinkytaco 9y ago
It's certainly been discussed in the forums I've read, and it could certainly account for some of it, but the mid-season spike in home runs starting in 2015 seems to point to at least one additional factor that would be somewhat consistent across all ballparks (including climate controlled). The balls seem to be one of the only factors that would account for that.
olympus 9y ago
Air density does have an effect, but the density change from temps that we've seen in the last few years (say a 75 degree game vs an 80 degree game) is only going to get you a couple feet of ball travel. While it make a difference on balls that just barely clear the fence, it definitely doesn't account for the entire boom in home runs. For comparison, a ball hit 400 ft at Yankee Stadium (400 ft elevation) would go 440 ft at Coors Field (5280 ft elevation). That's a 10% increase in ball distance for a 17% decrease in density. Increasing the temp by 5 degrees F drops the density by 0.8%, which is probably only good for 1-3 feet. https://chem.libretexts.org/Exemplars_and_Case_Studies/Exemplars/Sports%2C_Physiology_and_Health/Home_Run_Distance_and_Humidity https://chem.libretexts.org/Exemplars_and_Case_Studies/Exemp... https://wahiduddin.net/calc/calc_da.htm https://wahiduddin.net/calc/calc_da.htm

ofcrpls 9y ago

Similar discussion on cricket ball and how science shows no impact of weather on balls flying through air significantly enough but still remains a common misconception through out the sport's fraternity. http://theconversation.com/why-we-think-the-weather-affects-how-a-cricket-ball-swings-when-it-doesnt-46587 http://theconversation.com/why-we-think-the-weather-affects-...

stinkytaco 9y ago

It's certainly been discussed in the forums I've read, and it could certainly account for some of it, but the mid-season spike in home runs starting in 2015 seems to point to at least one additional factor that would be somewhat consistent across all ballparks (including climate controlled). The balls seem to be one of the only factors that would account for that.

olympus 9y ago

Air density does have an effect, but the density change from temps that we've seen in the last few years (say a 75 degree game vs an 80 degree game) is only going to get you a couple feet of ball travel. While it make a difference on balls that just barely clear the fence, it definitely doesn't account for the entire boom in home runs. For comparison, a ball hit 400 ft at Yankee Stadium (400 ft elevation) would go 440 ft at Coors Field (5280 ft elevation). That's a 10% increase in ball distance for a 17% decrease in density. Increasing the temp by 5 degrees F drops the density by 0.8%, which is probably only good for 1-3 feet. https://chem.libretexts.org/Exemplars_and_Case_Studies/Exemplars/Sports%2C_Physiology_and_Health/Home_Run_Distance_and_Humidity https://chem.libretexts.org/Exemplars_and_Case_Studies/Exemp... https://wahiduddin.net/calc/calc_da.htm https://wahiduddin.net/calc/calc_da.htm