East-West error at regular points on the Azimuthal Equidistant Map

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HELP ME get east west error for circles of latitude on the Azimuthal Equidistant projection as compared to the Globe.
Hello. I am conversing with Flat-Earth folks who tend to lean upon the Azimuthal Equidistant (AE) map centered on the North pole. I know that the AE map is a projection of the globe onto a flat surface, and is only accurate in distances north and south along lines of longitude. The east west distance error increases every mile away from the north pole, approaching silly amounts near the equator and Antarctic latitudes, and quickly increasing to infinity at the south pole. Can someone give me something that I can graph out on paper showing the (I suspect are exponential) error of east-west distances at multiple points between the north and south poles along circles of latitude? Perhaps give the distortion errors at 60N, 45N, 30N, Equator, 30S, 45S and 60 degrees south as a minimum (of course the east-west map error would be zero at the north pole, and infinite at the south pole). What measured distance error would be found for a short distance east and west at these points? Say along a 1 degree section? Is there a better way to do it?

Also. For a sphere with a circumference of 1 at its equator, what would be the circumference of the 30 degree, 45 degree, 60 degree north circles of latitude?
 
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Miles Behind said:
... Also. For a sphere with a circumference of 1 at its equator, what would be the circumference of the 30 degree, 45 degree, 60 degree north circles of latitude?
Earth circunferences.jpg
 
  • #3
Excellent! Thank you much! By the way, what would the value be for 15 degrees north?
 
  • #4
You are welcome.
For 15 degrees north the value would be simply 1.0 x cos (15) = 0.9659.
 

What is the East-West error at regular points on the Azimuthal Equidistant Map?

The East-West error on the Azimuthal Equidistant Map refers to the distortion in the representation of distances and shapes that occurs primarily in the east-west direction as one moves away from the center point of the map. This map projects the globe from a single point onto a flat plane, causing distances and shapes to be increasingly distorted the further they are from the center.

How is the East-West error calculated on this map?

The East-West error at any given point on the Azimuthal Equidistant Map can be calculated by comparing the actual east-west distance between two points at the same latitude with their represented distance on the map. This error increases as the distance from the central point of the map projection increases.

Why does the East-West error increase as you move away from the center?

As you move away from the center of the Azimuthal Equidistant Map, the scale of the map increases. This scale factor affects not only the distances but also the representation of areas and shapes. Since the projection is radial, distortions accumulate and become more pronounced at greater distances from the center, particularly in the east-west direction due to the stretching of the map along these lines.

Can the East-West error be corrected in the Azimuthal Equidistant Map?

While minor adjustments can be made to improve the local accuracy of the Azimuthal Equidistant Map, the inherent nature of the projection means that East-West error cannot be completely eliminated. For applications requiring high accuracy over large areas, especially in the east-west direction, alternative projections or geospatial analysis tools might be necessary.

Where is the East-West error minimal on the Azimuthal Equidistant Map?

The East-West error is minimal at the center of the map and along the meridian (north-south line) that passes through the central point. This is because the projection accurately maintains distances from the center to any other point along these lines, thereby minimizing distortion in the immediate vicinity of the center and along this meridian.

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