Meaning and Definition of Geographic Coordinate
Geographic coordinates are a system for locating specific points anywhere on Earth. The Earth’s mapping system through geographic coordinates expresses any horizontal position on the planet through two of the three existing coordinates in a spherical coordinate system, aligned with the Earth’s axis of rotation.
Therefore, the cartographic network offers the necessary conditions for the location to be possible. To find a certain point on the Earth’s surface, it is not enough for us to know whether it is in the East or West direction. It is necessary to use the geographic coordinates , which will provide more precision when locating.
Geographic coordinates can be understood as imaginary lines drawn on the globe, which are made up of parallels and meridians.
Geographic Coordinate Elements
The parallels are imaginary lines that cut the globe horizontally, and that are parallel to Ecuador. Ecuador is an imaginary circle that divides the Earth into two hemispheres, the northern and southern hemispheres.
The most important parallels are : the arctic polar circle and the Tropic of Cancer (northern hemisphere), in addition to the Tropic of Capricorn and the circle. Polar Antarctic (Southern Hemisphere).
In total there are 180 parallels, 90 to the north and another 90 to the south of Ecuador (0 °). Each of these is equal to 1°. Therefore, have 90º south and 90º north. They determine the latitudes.
Latitude is the distance in degrees from anywhere on the Earth’s surface to the equator.
Therefore, all places on Earth that are on the same parallel have the same latitude. When we know the latitude of a given point on the Earth’s surface, we can know in which hemisphere this point is located.
But, still we will not have the exact position , because for that we must also know the length of this point.
Meridians are imaginary lines that cut the Earth’s surface from one pole to the other. Unlike the parallels, which completely surround the Earth, the meridians only divide the planet vertically into two parts.
Therefore, there are also antimeridians, which correspond to the meridian exactly opposite any reference meridian. The most important meridian is Greenwich.
Thus, there are 360 meridians, of which 180 are located west of Greenwich and 180 are located east. Greenwich corresponds to 0º, and each meridian represents 1º.
Based on the meridians, it is possible to know the longitude of a given point on the earth’s surface.
Longitude is the distance measured in degrees from any point on Earth to the Greenwich meridian. This measurement varies from 0º (Greenwich) to 180º, for east or west.
Therefore, the set between the parallels and the meridians , provides information about latitudes and longitudes, forming a geographic network.
This network offers conditions to locate any point on the Earth’s surface. In addition, the creation of maps and graphs is possible with the knowledge of this data.
The geographic coordinate system is the oldest coordinate system. On it, each point on the Earth’s surface is located at the intersection of a meridian and a parallel. Its coordinates are latitude and longitude.
Therefore, for a precise location , it is necessary to match the latitude with the longitude of the location sought.