sgerhardt

Projected Coordinate System vs. Geographic Coordinate System

Discussion created by sgerhardt on Feb 28, 2011
Latest reply on Apr 18, 2016 by abdallah_91@yahoo.com
Hey everyone,

I'm new to the world of GIS so I was somewhat confused when I saw the option of choosing from either a geographic coordinate system or projected coordinate system in arcMap.

My first layer is a Landsat 5 image that reads as being in WGS_84_UTM_zone_15_N, which is a projected coordinate system in arcMap. I am trying to display a shapefile over this Landsat image, but the shapefile is in WGS84 which is a geographic coordinate system in arcMap. The input for the shapefile is in lat/long without regard to projection.

When I load the shapefile layer, arcMap gives me a warning that the coordinate systems differ, but the shape file still appears to be in the correct place.


So my main questions are:

1. What is the difference a geographic coordinate system and a projected coordinate system?

2. The shapefile is in WGS_84 and the Landsat 5 image is in WGS_84_UTM_15. Will this incorrectly affect the placement of the shapefile, or can I simply ignore this warning?

Any help would be greatly appreciated!

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