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I want to calculate the average value of a raster file within each polygon boundary of my shapefile. Because I want to preserve area I wish to use the Goode Homolosine (Land) projection. The original shapefile has a geographic coordinate system WGS1984, and the original raster file is also in WGS1984.

I used the Project tool to project the shapefile to the Goode Homolosine (Land) projection, and the Project Raster tool for the raster file, also choosing Goode Homolosine (Land) as the projected coordinate system.

It is my understanding that because both of the original files have a defined coordinate system, i.e., WGS1984, I should not be using the Define Projection tool.

Problem: When I open the newly projected raster file in ArcMap, I receive the following error message:

Warning, inconsistent extent!

One or more of the added layers has an extent that is not consistent with the associated spatial reference information.

Re-projecting that data in such a layer may lead to unexpected behaviour

Two things to note:

  1. I do not receive this error message when I add the newly projected shapefile;
  2. This error message occurs even when I add the newly projected raster file to an empty data frame (which, if I understand correctly, should automatically determine the coordinate system for me).

I have just spent a considerable amount of time reading on how to re-project data and cannot see any problem in what I am doing.

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Raster data: http://www.earth.columbia.edu/people/gmccord/sitefiles/file/malaria_ecology.zip Shapefile is not publicly available, but metadata states GCS_WGS_1984

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There is a bug in the Project Raster Tool. The output raster from the Project Raster tool is a little too big on the eastern edge, and on the southern edge (bottom of the easternmost gore/lobe). So the data extent doesn't quite match what the extent of a Goode's Homolosine projection is, and triggers the "not consistent extent" warning.

A workaround is to reproject the original raster in ArcMap and then export it using the data frame's coordinate system.

  1. Add the original raster to ArcMap
  2. Set the data frame's coordinate system to projected coordinate systems, world, Goode's Homolosine (Land).
  3. Right-click the layer's name in the table of contents and select Data, Export Data.
  4. In the dialog, use the raster's original extent, and the data frame's spatial reference. Update the output path and raster name. In my test case I left everything else the same.

Note: My first "answer" below was completely wrong, and I hadn't actually tried the OP's workflow when I wrote it. I think I see what happened, but I'm surprised that the Project Raster tool worked.

When I downloaded the raster, it has no defined coordinate system. I think the Project Raster tool failed silently and the output raster is still in WGS 1984 coordinates but has the Goode Homolosine defined. Go back to the original, use its property page in ArcCatalog or the Define Projection tool and set it to 4326 / GCS WGS 1984. Now use the Project Raster tool to convert it to Goode Homolosine.

  • Still can't get it to work. I re-downloaded the raster data, I then used the Define Projection tool and set it to GCS WGS 1984, and then used the Project Raster tool to covert to Goode Homolosine. And again when I open an empty data frame and add the projected data I get the same error message. I'm puzzled. Were you able to execute your suggestion without an error message? – acd Aug 26 '15 at 22:56
  • Just tried creating a tif, and no warning message. I did the cheater's method: added the original raster to ArcMap, set the data frame to Goode, exported the raster via data, export data (in the data frame's coordinate system). – mkennedy Aug 26 '15 at 23:10
  • Ah-ha, tool has different y min and x max values than using ArcMap export. Why? I don't know because the two tools are using the same projection code so it must be in the raster creation code somewhere. As a workaround, export the reprojected raster in ArcMap. I'll update my answer. – mkennedy Aug 26 '15 at 23:19
  • Your export method works! Thanks, your help is much appreciated. – acd Aug 26 '15 at 23:33
  • I am having a problem with your workaround solution using different data. I have posted about it here. If you have any advice I would greatly appreciated it, thanks. – acd Aug 31 '15 at 15:27
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The offered solution is incorrect. The error occurs when you forget to update georefencing. Once happened to me. After adding control point, go back and update georefence before defining the raster.

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    Welcome to GIS SE akj. I do not believe this is a georeferencing problem. Could you please expand on your answer to describe why control points should be used in this case? – Aaron Aug 19 '16 at 2:11
  • Thanks for your welcome Aaron. I did not say that ''control points'' should be used. I have encountered the problem described ahead. I could not get help in solving the problem. Until I realized my mistake. This mistake occurred me when I failed to update or rectify the georeference after picking the georeference points. Before you define the projection, please ensure you update the georeference from the georefence toolbar. – akj Aug 19 '16 at 21:43
  • @akj you mention 'adding control point' and georeferencing, which the original question doesn't mention at all. Also the solution that you think is incorrect has been marked as the correct answer by the asker of the question. If you don't believe it's correct please expand your answer, as Aaron suggests, to describe how your suggested solution would work. – Midavalo Aug 21 '16 at 22:45
  • @Midavalo, It was what I encountered and it was how I solved. If you ever encountered and apply my suggestion, if it fails, kindly let me know. – akj Aug 25 '16 at 15:17

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