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Results of Tabulate area and Zonal Geometry; total area are in red

Tabulate area results

I am working on Landcover map for Ghana. I calculated the area of each landcover type with Zonal Geometry in ArcMap. Then I wanted to know the area of landcover in each region (as in location). But when I used tabulate area in zonal statistics, the sum of total area for each landcover type among the regions was different from the one I had in using zonal geometry.

Please what could be the cause?

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  • Could you provide some screenshots / additional information of what difference occur exactly?
    – Jochen Schwarze
    Commented Mar 21, 2019 at 7:15
  • hi Jochen i have edited the post with screenshots
    – Mawuko
    Commented Mar 21, 2019 at 10:28
  • Perhaps read how zonal geometry assign cell size for analysis.
    – FelixIP
    Commented Mar 21, 2019 at 19:09

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Yes, your results look weird because both approaches are using rasters. One would expect similar decimal accuracy.

I did an experiment: converting integer raster to polygon with all environment settings pointing to original raster. I also ran Zonal Geometry as table on original raster. It took awful amount of time to complete and I don't like results:

enter image description here

Also "thickness" of 8551 m is way off the estimates from both raster and vector approaches:

enter image description here

So check what cell size is set in your processing environment and if still in doubt, stick to tabulate area results.

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  • the cell size is default
    – Mawuko
    Commented Mar 25, 2019 at 18:53
  • This is an issue. Change it to land cover one.
    – FelixIP
    Commented Mar 25, 2019 at 18:55

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