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Decimals are almost always used with metric measurements, and are associated with terms denoting length, weight, or volume, depending on the industry. Outside of formal schooling, however, you almost never hear about the geographical side of measurement - specifically, those ever-present invisible lines of latitude and longitude.

How are metrics shown in geographical terms? Who uses traditional Degrees/Minutes/Seconds? How popular will decimals and geographic metric measurement be in the future?

== American Metric History ==

Originating in France in the 1790s, the metric system (officially known as "SI", short for "Le Systeme International d'Unites") grew in popularity due to increasing global commerce. Through trade with Europe, the U.S. awareness of metrics trickled into existence, eventually prompting Congress to permit its use in 1866. It was legal, but voluntary.

The first official metric conversion legislation was passed by congress in 1974, adding metrics to our elementary and secondary education curriculum. One year later, Congress passed the Metric Conversion Act, declaring that the U.S. federal government use metrics as its preferred measurement system. (i.e. The nutritional information on any package of food shows grams instead of ounces.)

Ever since its beginnings, the U.S. government has striven to promote and stabilize metrication, with limited results: Mostly those in the sciences, military, manufacturing, and other technical fields use the metric system. The general public, however, continues to show comparatively overwhelming disinterest in adopting grams, liters, and meters over the traditional ounces, quarts, and feet. The United States is the only remaining industrialized country whose general population does not use metrics as its primary measurement system.

To learn more details, dates, and other information about metric measurement, visit the U.S. Metric Association (USMA) web site (http://lamar.colostate.edu/~hi llger/.

== Metrics And Geography ==

Despite the average American's apathy for metrics, those who use geographic coordinates on a daily basis see plenty of evidence that decimals are out in full force. On any given day cartographers, engineers, geographers, surveyors, and other in the earth-related sciences will see data with a decimal somewhere in the latitude or longitude.

As technology has developed over the years, allowing more accurate measurements, the number of digits on the right side of the decimal point is getting bigger. This improved technology has also allowed folks in geographically inclined occupations to read those coordinates in different ways. The three most popular types of latitude/longitude displays are:

1) Traditional degrees/minutes/seconds (D/M/S), usually with decimal seconds

2) Degrees with decimal minutes, no seconds

3) Decimal degrees, no minutes, no seconds

== Doing The Math ==

No matter how you choose to display them, any converted coordinates will get the same answer - it's simply a matter of preference. If you are one of those people who grew up learning only Degrees/Minutes/Seconds, you might break into a cold sweat the first time you see the second or third decimal variations above, if only from the memory of your high school algebra classes.

Fear not, for there are numerous conversion programs and web sites that will do the math for you. A majority of these sites convert between D/M/S and decimal degrees, leaving out the less popular but still available decimal minutes. One of such site belongs to the Federal Communications Commission (FCC) (http://www.fcc.gov/mb/audio/bi ckel/DDDMMSS-decimal.html.

Ther e are other sites for those who don't mind math, or who are naturally intrepid souls that wish to brave longhand algebraic equations. If you are ready to break out the Texas Instruments calculator and go for it, you might try the Montana Natural Resource Information System (http://maps2.nris.state.mt.us/ topofinder1/LatLong.asp, which shows conversion equation examples, but also provides an automatic converter.

== Finally Rubbing Off? ==

During the 2000s, more and more Americans seem to be warming up to the concept and have begun using decimals in their everyday lives. Certainly the growing number of metric labels on many foods, drinks, health care items, cleaners, and other various products are clear indicators that the average American consumer should start learning to accept decimal numbers.

This goes for geography as well. GPS unit sales to the nonmilitary population are on the rise and most (if not all) GPS units display a location using decimals. One can expect hiking, boating, driving, or any other type of navigational information to be in this same format, no matter the scale, map projection, or elevation.

As the rest of the world moves forward with metric standards, the United States government may feel more pressure (especially from Europe) to go totally metric for global trading purposes. Once the population finally accepts that change is coming, decimal numbers will be even more abundant and it will filter down through every aspect of American industry.

== Don't Panic ==

For those hikers, boaters, drivers, orienteering students, architects, and others who may be used to using only Degrees/Minutes/Seconds, don't worry. The conversions are out there, and it's easy to get results from them.

American society is experiencing a slow switch from traditional to decimal measurements, but if you're loyal to the older ways, you can always rely on latitude and longitude lines. They certainly aren't going anywhere.

Learn more about this author, Len Morse.
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