Today's time zones really are archaic. To truly be accurate one should adjust their timepiece per location. I saw a time piece sometime back that was running for around $600 that did just that by using a GPS. IIRC the time was changed constantly, but because of the true accuracy was so great, it was actually inaccurate.
For example- In West Wendover Nevada it is the same time as Sacramento California, let's say 12:00 noon. 1/2 mile away, in Wendover Utah, it's now 1:00 pm. 500+ miles away in Paxton Nebraska, it's 1:00 pm. 12 miles away in Sutherland Nebraska, it's now.....2:00 pm.
To be truly accurate, at the least a time piece should be adjusted every 15" East-West. At the equator one degree is roughly 60 miles. But as you travel north or south, the distance between say, 39 degrees and 40 degrees decreases because of the proximity to either pole. Best way to understand this is to look at an actual physical globe.
In theory the time zone is truly accurate in the north to south center-line of the zone. Which really sucks when you look at how the time zones have such diverse boundaries. IIRC the fish and game of a respective area has a formula for that area in deciding the true time based on distances from given points.
Edited by LilacLouie (07/30/09 11:50 AM)