klglennon

very low area values from calculate geometry in ArcGIS10

Discussion created by klglennon on Oct 4, 2012
Hello,

I've been trying to calculate geometry (specifically area) for polgyons that are projected using World_cylindrical_equal_area (WGS84
for GCS). The data originally comes from an ascii file, that I convert to raster, which I then convert the raster to a polygon (shapefile). Once I have the shapefile, I project it in a new map and define the projection to use an equal area projection. In one desperate attempt, I calculated area using the geodatabase, however, the result is much less than expected, e.g., the size of Texas is not 174 sq m. Alternatively, if I use the calculate geometry tool in the Attribute table, I get 0.000, or 0.0000024 for my polygons. There has to be an issue or a step I'm missing when projecting the polygons with the projected coordinate system, but I cannot seem to figure it out. Any help or insight would be greatly appreciated!

Thanks!
kelsey

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