I have a vineyard boundary and am trying to get an estimate of acres that are below 200 m elevation for insurance purposes (these areas are more prone to frost damage). Rather than dealing with a DEM can i just use a topographical map to intersect below 200m? and if so where can i get a raster version? Any help is appreciated! thx
You could digitize the contours from the toposheet with attributes (Elevation). Then Interpolate the contours to create an Elevation Raster (using the Elevation Field of the Contours).
You could then use Raster Calculator to extract the Raster Values < 200 m.
Convert the Raster to Polygon, and intersect the Polygon with the Vineyard boundary polygon.
The resulting polygon is the area of the vineyard below 200 m.