A layman’s guide to understanding Latitude and Longitude.

There are hundreds of web sites out there describing Latitude and Longitude, and I’m sure they are filled with great information; at least the ones I looked at were.

Anyway here are a few bullets.

Lines of Latitude run north and south but are measured east and west.
Lines of Longitude run east and west but are measured north and south.

One degree 60 minutes
One minute equals 60 seconds.
One minute equals one nautical mile.
One nautical mile equals 2000 yards; more or less.
That means, if my math is right, that one second equals 33 yards; more or less.

Latitude and Longitude are written in different ways.
Degrees, Minutes and Seconds. 55° 34’ 53”N
This can also be written in Degrees and Decimal minutes. 55 34.88 N
Also written in Decimal Degrees 55. 581389N
Any one of them will work but GPS units other electronics will be into the decimals.
As you can see converting the example from seconds to a decimal with six numbers to the right let will place you on a spot on a dime.
Here’s a handy conversion site. Decimal conversions When using this you have to enter the coordinates as degrees, minutes, and seconds. Now days the vast majority of coordinates are written in degrees and decimal minutes, so you have to do some math. Using the example above 55 34.88 we multiply .88 by 60 and come up with 52.8 round that up to 53 Seconds.
With all lat/long written in decimal degrees there was a need to define what coordinates are North South East and West. Here it is. All coordinates east or north of the equator are positive numbers. Those south or west are negative. When writing a position using the degree decimal format any negative coordinate is preceded by a minus symbol “-“
Example:
56.926667 -132.485278 This coordinate is North and West

-07.82312 -133.76954 South and West

-5.345654 147.1211 South and East.

22.78765 30.45321 North and East.

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