Effects of altitude on a baseball pitch.
As stated ealier, most people are aware of the differences in flight distance of a baseball, football, or golf ball between sea level and the altitude of Denver, Colorado, which represents the extreme altitude for many sports. The increments between these locations also affect the flight due to air resistance and, therefore, the amount of ball movement for many other cities. In this representation, we have selected 1,000 feet elevation in comparison to sea level. One thousand feet represents a number of teams, including Arizona, Atlanta, Kansas City, Texas, Minnesota, Milwaukee, Chicago, Cleveland, Cincinnatti, Pittsburgh, Detroit, and the Chavez Ravine. The difference in ball movement from elevation alone is shown here.
"Actual Barometric Pressure"
One of the most significant issues for baseball people to understand is actual air pressure. The hidden truth about pressure is hidden from the public by the media, because meteorologists speak of barometric pressure from a "sea level" measurement. Meteorologists must present a clear picture of air pressure highs and lows so that they can keep a watch on the small daily pressure changes within "all" altitudes across the nation and around the world. Therefore, they have adjusted the standard air pressure at all locations to "sea level", but this does not represent the "actual pressure" for the location.
In order to adjust the standard seal level pressure measurement of 29.92 inches of mercury to the actual pressure at differing altitudes, one must subtract approximately 1 inch of mercury for every 1,000 feet of altitude. Therefore Phoenix, AZ would normally read approximately 28.92 actual barometric pressure; Las Vegas, NV at 2500 feet in elevation would normally read about 27.00 inches of mercury; Lubbock, TX air pressure would be represented at about 26.50 inches of mercury; and Denver, CO normal air pressure is actually measured at 25.42 inches of mercury. See our discussion about "Air Weight" for a better understanding of the difference between altitudinal air densities. The air resistance against the baseball cover and stitches causes the pitch to curve, hop and especially to "Lift" on a four-seam fastball. Each 1,000 feet of altitude above sea level "at the same temperature" will take 1 inch of upward lift away from any major league pitcher's fastball.
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This representation was provided to Clifton Neeley by Paulin Research, Houston, Texas, Mr. Tony Paulin, PE. The program utilizes physics formulas from the Physics of Baseball, by Dr. Robert Adair as well as studies by doctoral program students and known formulas in the engineering and aeronautics industries. The depiction is similar to a point to point launch of a ballistic missile or other projectile, converted to match the cover, weight, shape, density and circumference of a spinning baseball projected through the properties of natural air. Sincere thanks to Mr. Tony Paulin.