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I've got a shapefile which already has a projection, and whose GCS is WGS 1984. When I add it to a blank map document I get:

Warning! Inconsistent extent! error.

The extent of the shapefile is bizarre. How can I clear the .prj file and correct the extent? At this time I don't need actually need it in a specific projection. Here's the extent:

Top: 1647192.701300 dd

Bottom: 388436.828700 dd

Left: -35734.283900 dd

Right: 940661.882900 dd

PolyGeo
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406LQE
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    What location does the data represent? – mkennedy May 06 '17 at 21:36
  • @mkennedy Ethiopia. The data was given to me and I've been unable to locate the metadata or any information on the projection. – 406LQE May 08 '17 at 12:49
  • The values are matching really closely with UTM zone 37N (North). We can't tell which geographic coordinate reference system though. Try WGS84's, 32637. – mkennedy May 08 '17 at 20:10
  • @mkennedy The shapefile itself says the GCS is already defined as WGS1984, so it should be fine, right?

    Thanks a lot for your help. How were you able to narrow it down?

     – 406LQE May 08 '17 at 21:06
  • Hopefully, it will be fine! But someone managed to define it as a GCS, when it isn't, so...I used ArcMap--add a world basemap with country boundaries, set the data frame's coordsys to what it could be. The coord ranges look like UTM to me. UTM X should be 200k to 700k, but if one zone was used for a whole country, then you'd see extents like yours. For UTM Y, 10 degrees of latitude are about 1million meters. – mkennedy May 08 '17 at 22:10
  • @mkennedy Thanks for the explanation. I'm returning to GIS after several years off, so I just want to be sure I'm understanding correctly. I can see the shapefile has a .prj, and when I add it to a blank map document I only saw a Geographic Coordinate System in the Properties>Source>Data Source; there was no projected coordinate system. Is that because, like you said, they had actually managed to define BOTH the geographic and projected coordinate systems as GCS WGS 1984? – 406LQE May 09 '17 at 13:13
  • No, someone just picked a gcs, when it should have been a pcs. Sometimes people use define projection/data properties to set the coordsys to what they want it to be, rather than reprojecting correctly. – mkennedy May 09 '17 at 13:44
  • @mkennedy Ok, I think that makes sense. By the way, what do the numbers 32637 reference? – 406LQE May 09 '17 at 20:10
  • It's a well-known ID, WKID. The EPSG Registry keeps a set of coordinate reference systems and transformations. Each one has a WKID. They've become somewhat common to use, particularly with web services. ArcGIS supports most of them, and you can select a CRS by browsing a directory structure or by the WKID. 32637 is WGS84 UTM 37N. – mkennedy May 09 '17 at 21:18
  • @mkennedy Thank you so much, you've been a huge help! – 406LQE May 11 '17 at 12:40
  • Thank you! This kind of back and forth isn't really appropriate here and I'm surprised no one's told us to take it to chat. It's better fitted for Esri's geonet. – mkennedy May 11 '17 at 12:47

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Those coordinates are clearly not consistent with a geographic coordinate system.

The numbers should be representing a projected coordinate system instead.

You will need to determine the projected coordinate system that they are derived from and then use Define Projection to define that coordinate system on your shapefile.

If you need help determining the coordinate system, see Identifying Coordinate System of Shapefile when Unknown?

PolyGeo
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  • Can you suggest some ways of determining the projection? Also, shouldn't the Bottom extent coordinates be negative? – 406LQE May 08 '17 at 12:50