TIME IN THE ZONE
A brief history of the U.S. Department of Transportation's configuration of time zones.
With the 2019 fall release of the National Transportation Atlas Database, a new map of the nation's time zones is featured, showing the geographical boundaries of four time zones in the continental U.S. and the time zones used in Alaska, Hawaii and other U.S. territories. These time zones, with boundaries that have for the most part been fixed for more than a century, are taken for granted by most Americans. But that has not always been the case. Keeping the trains on time
Before the establishment of time zones in 1883, there were more than 144 times in North America. The resulting small time differences between adjacent towns and cities were not critical when it took days to travel from place to place. With the proliferation of railroads, faster travel became possible across many cities and travelers could sometimes arrive at an earlier local time than the one they had left. Due to this lack of time standardization, schedules on the same tracks often could not be coordinated, resulting in collisions. The major railroad companies as a result began to operate on a coordinated system of four time zones starting in 1883.
Creating the zones
Standard time was transportation-driven and, as a result, the government coordination of time zones was handled by transportation agencies. The federal organization in charge of railroad regulation – the Interstate Commerce Commission – was given the power to address coordination concerns in 1918. That year, five time zones were officially adopted as the US entered World War I: the Eastern, Central, Mountain, Pacific and Alaskan zones still in use today. However, the need for coordination among all modes became increasingly important after
World War II. When the Department of Transportation was founded in 1966, the responsibility of regulating standardized time was transferred to it.
Daylight Saving Time is another responsibility of the Department of Transportation PHOTOSPHERE and has become more widespread for reasons of It energy is here savings that the and economy. Today, the Department of sun's Transportation radiation continues is to supervise standard time due detected to its historical as sunlight. and contemporary importance in 10,000 transportation degrees and associated commercial activity.
Daylight Saving Time is observed uniformly across the nation with the exception of four territories and two states (Arizona and Hawaii). SUN Time SPOTS zone boundaries are also established by law and Cooler can only areas be of changed sun. by the Secretary of Transportation The if number the adjustment of spots is deemed to benefit commerce. varies with a cyclic
Over the past two decades, period 15 communities of about 11 (counties, cities and parts of counties) years, have known changed as their the time zone boundary, the most recent sun cycle. being Mercer County in North Dakota. It switched from Mountain to Central
7,300 degrees
Time in 2010.