Saturday, January 16, 2010

Why Indiana children wait for the school bus in the dark

After reading a couple of recent letters to the editor from fellow Hoosiers, I remembered that I wanted to do an update corresponding to my "earliest sunset of the year" post on December 7.

In the South Bend Tribune on January 12 (When will Indiana students see the light?), Angela Warren-Manns wrote:

"I am concerned for my son who has to be out in the dark to go to school in the morning. This is bizarre for us because where we are from in New Jersey, it is light outside around 7 a.m. We have also lived in Texas, California and Maryland and they are also the same as New Jersey: light around 7 a.m. It just doesn't make sense to me that Indiana is on Eastern time. The sun certainly does not agree with it."

Ms. Warren-Manns is quite correct. The average sunrise time for places due east and west of South Bend on January 12 is 7:25 am. Civil twilight (when there is sufficient natural light for terrestrial objects to be clearly distinguished) is about 7 am this time of year for places in the geographically correct time zone.

In the Montgomery County (Crawfordsville) newspaper (Who makes decision on delays, closing?), Buddy Posthauer writes:

"My daughter has not had very much experience driving under these conditions... She could have taken the bus which picks her up about one hour earlier than when she drives, which it is pitch dark, and although this is not the schools fault, thanks to the time change, no child should be standing along side a busy and dangerous highway in the dark, even if the weather is good. It was just a few years ago I could not leave for work on time because a gentleman lost his life after a head on collision right where the kids have to stand in the dark to wait on the bus, which is much more dangerous in bad weather."

What both of these letters have in common is that they highlight the increased risk to Indiana children on their way to school this time of year because of observing eastern time.

Except for a few counties in the northwest and southwest corners, all of Indiana has been in the geographically incorrect eastern time zone since the 1960s.

January 4 marks the latest sunrise of the year.

The natural clock time (aka Local Mean Time) for sunrise in Indianapolis on January 4 is 7:22 am. This would be the sunrise time on January 4 if Indianapolis had ended up at the middle of a time zone like Philadelphia or Peoria did.

The table below compares the sunrise time on January 4 in Indianapolis with other United States cities located in their geographically-correct time zone.

On eastern time, Indy sticks out from the pack like a sore thumb. It will be back in the normal range again whenever Indiana goes back to central time.

Sunrise times on Monday, 4 January 2010

8:06, Indianapolis (eastern time)

7:23, Philadelphia (middle of eastern time zone)
7:23, Peoria (middle of central time zone)
7:21, Denver (middle of mountain time zone)
7:20, Reno (middle of Pacific time zone)
7:20, New York City
7:18, Chicago
7:14, Boston
7:06, Indianapolis (if returned back to central time)
6:59, Nashville TN (nearly due south of Indy)
6:52, Las Vegas

Ref: http://www.usno.navy.mil/USNO/astronomical-applications/data-services/rs-one-year-us/

5 comments:

CivicMinded said...

The real issue is that people need to drive carefully, and changing Indiana back to central time will not help that. Why don't you move to Illinois if it bothers you so much.

Bill Starr said...

Thanks for your comment. We agree that driving carefully is important, but travel experts agree that driving without the benefit of daylight presents additional challenges.

Safety Tips for Driving at Night : Road & Travel Magazine

If Indiana were back in its natural time zone again, that would give the morning drivers and children walking to school and waiting for buses an extra hour of daylight, which could be a big help.

The time zone is not sufficient reason to consider moving to the next state, but finishing the job of fixing Indiana's time zone would help improve the quality of life here even more.

Fri, 22 Jan 2010, 6:17 am EST

Bill Starr said...

For anyone who may not be familiar with the natural time zone boundaries, everyone on eastern time sets their clocks to Local Mean Time (LMT) for 75 degrees west longitude during the non-DST months. This is the natural clock time for Philadelphia.

Everyone on central time sets their clocks to LMT for 90 degrees during the non-DST months. This is the natural clock time for Peoria.

The natural boundary between eastern and central time is midway between at 82.5 degrees. This line runs north-south through the middle of Ohio. So all of Indiana, the western half of Ohio, and virtually all of Michigan, Kentucky, and Tennessee lie in the natural boundaries for central time.

It's pretty easy to see why Ohio would have wanted the federal government to shift the time zone boundary to its western border, so the entire state could set their clocks to the same time.

With Indiana's clocks already all naturally on central time, it's harder to see why anyone thought it was a good idea to ask the federal government in the 1960s to move the boundary halfway across Indiana and split us into two different time zones.

Bill Starr said...

This page has a nice map showing the time zone boundary running right down the middle of the state from 1961 to 1967, just after Indiana changed from a single time zone to two zones.

Time in Indiana - Wikipedia, the free encyclopedia

Bill Starr said...

There is a corollary to my comments above about the local mean time of Peoria and Philadelphia.

During the 7.8 months of DST (from 2 am the second Sunday of March to 2 am the first Sunday of November), everyone observing central time sets their clocks to the local mean time (LMT) of 75 degrees west longitude. This is the natural clock time of Philadelphia.

Likewise, everyone observing eastern daylight time, including Terre Haute, Indiana, sets their clocks to the LMT of 60 degrees. This is the natural clock time of Goose Bay, Labrador. This finding was somewhat shocking to me when I first checked it on a map.

It takes the sun about 110 minutes to travel overhead from Goose Bay to Terre Haute (105 minutes for Indianapolis; 100 minutes for Richmond). This figure also corresponds to the average number of minutes of daylight shifted from morning to evening during the DST months.

On average, only 60 minutes of daylight are shifted from morning to evening in all the places that are in their natural, geographically-correct time zone.

This helps to explain the somewhat freakishly late fall, winter, and spring sunrises and summer sunsets in the Indiana counties still on eastern time, as compared with places more or less due east and west of Indiana (i.e., about the same total amount of daylight as Indiana) where you may have visited or lived.

Fri, 22 Jan 2010, 12:42 pm EST