While I creat flood areas using DEM in ArcGIS, Which parameters do I consider to determine DEM's pixel size and resolution?
DEM pixel size is based of your topographic map scale . DEM pixel size that calculate using topographic map with 1:25000 scale has 10 * 10 meters pixel size. For 1:50000 scale the pixel size must be 20*20 meters and so on.
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