how are the time zones in the us determined?

Question

the time zones don't seem to follow any "state" lines in many states, wondering what the determining factors are.

Answer 1

The local and state governments do NOT decide where the time zones are. This is done by the US government, specifically the Department of Transportation is responsible for time zone boundaries. The primary factor is the convenience of commerce; some others are energy savings, traffic fatalities, school-age children safety, crime, and effect on radio audience share.

For example, when parts of Indiana wanted to change to Central Time, (in 2006) they had to ask the Dept. of Transportation to change the boundaries.

A state can chose if they want to observe daylight saving time or not; and if a time zone line goes through the state, they can pick daylight saving time for one zone and not the other.

Answer 2

They were started so that the transcontinental railroads could be scheduled with consistency, over a hundred-odd years ago. There was a sort of general longitude chosen for each - and then the towns and counties along these meridia got permissions to jump to one side or the other. Ultimately it's determined by states and towns today - though within limits... Utah can't suddenly decide to be Eastern Time Zone, but might choose to switch between Pacific and Mountain. In fact, Arizona does exactly that every year.

It's not really as messy as it looks, though.

Answer 3

In general, the time zones do follow state lines.

The time zones of the United States are standardized by Congress and although the lines were drawn to avoid populated areas, sometimes they've been moved to avoid complication. There are nine time zones in the U.S. and its territories, they include Eastern, Central, Mountain, Pacific, Alaska, Hawaii-Aleutian, Samoa, Wake Island, and Guam.

With the growth of the Internet and global communication and commerce, some have advocated a new worldwide time system.

It is interesting to note that although China spans five time zones, but only uses one time for the entire country.

Answer 4

Established at an international convention in 1883 held in Washington, D.C. At that time Greenwich was also selected as the zero or Prime Meridian in deference to Gr. Britain which at the time had the world's largest maritime fleet and also its worldwide Empire which as Kipling noted, was the "Empire upon which the sun never set." Prior to that time a place like Chicago the nation's center for major railroads, had as many as 12 time zones due to the railroads each maintaining their own time clocks. To rid the nation of the confusion largely created by all the many U.S railroad companies' practice, the U.S. Gov't ( now its Dept. of Transportation) readily ascribed to the conventions adopted at that 1883 conference of nations.

Answer 5

The railroads determined time zones in the 1870s or so in order to schedule train traffic. They didn't care about state lines.

Answer 6

The true time zone should every 15 deg. of earth rotation. The local gov. changes it slightly so that the hole state is on the same time.

Answer 7

They basically follow the imaginary longitudinal lines on a globe.

Answer 8

Magic.

~Neeva

Answer 9

the sun. the earth rotates. so the time is different because we all cant be at the same place at the same time.

Answer 10

POLITICS!!!!!!!!!!!!!!!!!!