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elevation area, slope gradient area, slope aspect area

March 07 2011 | 0 comments
Categories: ArcGIS Methods, Map Data

How can i create three polygon feature showing elevation area, slope gradient area and slope aspect area based on a elevation contour polyline shapefile?  Can you also point out possible loss of data with each step? We have ArcMap 10 and spatial analyst. Thank you.

Mapping Center Answer:

This is best done with raster data rather than vector (polygon) data.  You can create an elevation raster from the contour shapefile. And then from that you can create the slope and aspect rasters.  If you wanted, you could then convert the elevation, slope and aspect rasters to polygon feature classes.  You would introduce some loss of data in the raster to polygon conversion if you decided you wanted to do any generalization. However, the most loss of data will occur in the conversion of the contour lines to a raster surface as you will at this point have to choose a resolution for the resulting elevation raster.

Use the Topo to Raster tool to create the elevation raster, then use the Slope tool and Aspect tool to make the other rasters.

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