Words on Weather & Climate — April 8, 2010

Time zones

by CRAIG JAMES

I think most of us understand the basic times zones across the county. In the lower 48 states there are the Eastern, Central, Mountain and Pacific time zones. However, before the advent of railroads, each city in the country had its own local time that was set to solar noon (when the sun is directly overhead). Since the sun is directly overhead about one minute later for each 12 miles you travel to the west, traveling on horseback didn’t usually cause much of a problem. Your watch was only a few minutes off after a day’s travel.

However, when railroads began moving people long distances in a short period of time, railroad time schedules became very confusing. In the 1860s, the railroads were dealing with over 300 local time zones. In 1884, the concept of standard time zones, each spanning approximately every 15 degrees longitude, was implemented worldwide. Where time zone lines ran through cities, the lines were nudged either west or east so the entire city was on the same time zone.

But some states ended up in two time zones. The state of Indiana has 92 counties; 80 are now in the Eastern Time Zone and 12 are in the Central Time Zone. When Daylight Saving Time (DST) was implemented during World War I, all counties in each state were required to use it year round. This experiment in DST lasted just seven months, but was reinstated during World War II. After the war, between 1945 and 1966, each county, led by the wisdom of its own politicians, decided whether to stay on DST or not. In Indiana, 15 counties adopted DST and 77 did not.

If that had happened in our area, it would be like Grandville being one hour ahead of Jenison, but for only part of the year. Finally in 2006, Indiana adopted DST in all counties. Arizona does not go on DST except on a few Indian reservations.

It took me a while when I moved to Grand Rapids to get used to the fact that the National Weather Service does not adopt DST. When they post the daily climate summary in the winter, it is for the 24-hour period from midnight to midnight, but when we are on DST, it is from 1 a.m. to 1 a.m. I have seen it rain hard between midnight and 1 a.m. local time in the summer and the rainfall amount always shows up as having fallen on the previous calendar day.

There are some countries in the world that do not use standard time zones, such as Iran and India. In most of the world, as you move from one time zone to another, the change is exactly one hour with the minutes staying the same. In these countries, their time zone differs by just 30 minutes. In Nepal, the difference is 45 minutes. So if you go from Nepal to India, staying in the same time zone, the difference is 15 minutes.

Russia has 11 different time zones but stays on DST year round. China is big enough to have five time zones, but has chosen to only have one. That would be like traveling from Boston to Fairbanks and staying in the same time zone.

The International Date Line really confuses things. The International Date Line is an imaginary line, which basically says, as an example, on one side of the line when it is Wednesday on the other side of the line it will be Thursday. The country of Kiribati consists of a group of 33 coral islands near the Equator and straddles the dateline. To solve the problem of having one part of Kiribati be on one day and the other part of the country on another day, the government has decided to ignore the International Date Line and keep the whole country on the same day, albeit in three different time zones.

Christmas Island, which is located in the most eastern part of Kiribati, is in the same time zone as Hawaii. Yet, when it is Thursday on Christmas Island, it is still Wednesday in Honolulu, even though they are in the same time zone and even though Christmas Island is basically directly south of Honolulu!

Since time zone lines converge at the poles, when you realize your lifelong dream of traveling to the North Pole or South Pole, you could actually walk through all 24 time zones in just a few seconds by simply turning around.

What actually happens in Antarctica is the country that operates the research station there determines the current time. So a Russian research station would most likely have the same time as Moscow and a British research station might have the same time as London and so on. The U.S. stations all use New Zeeland time, since flights to Antarctica all leave from Christchurch, New Zeeland.

You will be given a test on this information next week!

Craig James has been retired since July 1, 2008, after 40 years of broadcasting television weather. He was chief meteorologist at WZZM-TV for 12 years and chief meteorologist at WOOD-TV for 24 years. He is a graduate of Penn State University, where he received a Centennial Fellowship Award. He was also honored as a Fellow of the American Meteorological Society.

About Squire News

The Squire has been Rockford’s free weekly newspaper since 1871. Our loyal readership includes over fifteen thousand homes in the Rockford area, including the affluent Lakes area of Lake Bella Vista, Bostwick Lake and Silver Lake; Belmont, Blythefield, as well as Algoma, Courtland, Cannon and Plainfield Townships. The Squire is distributed through the U.S. Post Office every Thursday. We also deliver to in-town businesses and homes with paper carriers and news stands in our grocery stores and over thirty local shops.
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