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Am shyaka from Rwanda.
I use GIS tools and have all required data to perform or calculate surface area from the polygons that have been given by GPS (Trimble) with ArcPad 8.
I originate from a high land region when I map a polygon with different hills, talwegs and when I tried to calculate the surface area using ArcMap in ArcEditor 9.3 just the area becomes too small compare to the decameter.
However, this area does not come from DEM (i.e. I did not use DEM to calculate the area). It is a big problems for me to handle this issue of surface area. I need really your help.
It will be good if you can provide the procedures for how to do this.