Exploring geographic coordinate systems
A geographic coordinate system (GCS) leverages a three-dimensional spheroid surface to define locations on or above the Earth’s surface. These locations are identified based on their longitude and latitude values. In most geographic information systems, you will see longitude represented by an X value and latitude represented by a Y value. Points that are above the Earth’s surface have a Z score representing their altitude above the surface. Longitude and latitude are angles that span outward from the center of the Earth. The angles are often measured in degrees (°) of the circle, where the entire circle is 360 degrees.
The network of latitude and longitude lines is known as a graticule, as shown in the following diagram:
Figure 3.2 – A graticule network
Figure 3.3 shows the Earth with a graticule network based on a GCS.
Figure 3.3 – The Earth with a...
