"dd" in numbers typically refers to "decimal degrees", a unit of measurement for latitude and longitude.
- Latitude measures the distance north or south of the Equator.
- Longitude measures the distance east or west of the Prime Meridian.
For example, the coordinates of the Empire State Building in New York City are 40.7484° N, 73.9857° W. This means it's located approximately 40.7484 degrees north of the Equator and 73.9857 degrees west of the Prime Meridian.
Decimal degrees are a convenient way to express latitude and longitude because they offer greater precision than degrees, minutes, and seconds.
Here's how to convert from degrees, minutes, and seconds to decimal degrees:
- Divide the minutes by 60.
- Divide the seconds by 3600.
- Add the results of step 1 and step 2 to the degrees.
For example:
- 40° 44' 54" = 40 + (44/60) + (54/3600) = 40.7483°
Note:
- When using decimal degrees, you always include the degree symbol (°).
- You also need to specify whether the latitude is north (N) or south (S) and whether the longitude is east (E) or west (W).
