From SABR mmeber Wendy Thurm at FanGraphs on June 21, 2012:
Yesterday was the first day of summer. Temperatures were above-average throughout most of the country. In cities hosting MLB games, temperatures were 5-15 degrees above normal, save for those games played in the paradise known as the California coast. There were 42 home runs hit in MLB games yesterday. These facts are likely related.
First things first. Yesterday’s home run tally did not break the record for most home runs hit by all MLB teams on a single day. That record is 62 home runs, hit on July 2, 2002. We’ll come back to that in a bit.
A few weeks ago, [SABR member] Alan Nathan, a Professor Emeritus at the University of Illinois-
Champaign who studies the physics of baseball, provided a more detailed description of the relationship between high temperatures and home run production. Nathan wrote the article in response to Tim McCarver‘s recent comment during a FOX broadcast of an MLB game that global warming explains the rise in home runs in the 1990s and early 2000s.
Read the full article here: http://www.fangraphs.com/blogs/index.php/as-temperatures-soar-so-do-the-home-runs
Originally published: June 22, 2012. Last Updated: June 22, 2012.