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I work in WGS 84 (Geographic Coordinate System) in ArcGIS 10.1. I need to create a raster specifying its cell size in meters, and output it in WGS84.

Is it a good solution (towards a less shape/area distortion of the final result) to proceed in this way?: Create the raster from the shape which is in a Geographic CRS (WGS84), having set before the CRS of the Data Frame to a projected one (WGS84 UTM) in order to be able to give cell size in meters, which be a small value in relation with the actual required resolution in order to get accurate result when the expected resampling happens; then, once the raster is in a projected CRS, reproject it to WGS84 (the resampling is expected that involves a low shape/área distortion)?

IMPORTANT for this implementation to be practical: In the last step (reproject the raster to WGS84), when specifying the Cell size of the resulting projected raster, the units of the default value that appears are decimal degrees. Are this value coincident with the Cell size in meters of the raster from which I am projecting to WGS 84?

Another related doubt to solve: Which would be the proper projected coordinate system through the raster would pass, better than WGS84 UTM? A equal area one? an equal distance one? Or would UTM (which is a equal shape one) be the best?

  • It depends on what you are trying to achieve. Why not use a metered system based on WGS 1984? SR-ORG:7143 or SR-ORG:45? But it really depends on why you are doing this. The flow above seems unnecessarily convoluted. – If you do not know- just GIS Sep 26 '14 at 12:06
  • Thank you. I really need to work in WGS 84 (Geographic coordinate system) because I have to output the results in that CRS. Thus, I can't work in a metered system and unproject to WGS84 at the end without distortion (as far as I am concerned). – Charly Sep 26 '14 at 17:16
  • maybe you should merge this question with the previous one gis.stackexchange.com/questions/114648/… – radouxju Sep 26 '14 at 19:49
  • and I think that your problem is that your polygon that looks OK is probably distorted in reality, because what you see on screen with a WGS 84 coordinate system is a bijection (like Plate carree) between lat/long coordinate and screen coordinates, not the real object on the ellipsoid. – radouxju Sep 26 '14 at 19:59

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