The various tasks for module 7 have taught us ways to aid map viewers in visualizing the terrain that is being displayed. One of the more precise methods is to display and label contour lines; such maps are familiar to hikers and anyone familiar with USGS map products. Another method is to apply hillshade to a DEM (digital elevation model). Hillshade tools, such as provided by ArcMap, take the elevation data of a DEM and simulate the visual effect of the sun at a specified angle and direction. This visual effect greatly aids the viewer in reaching an intuitive understanding of the topography of the displayed area. Hillshade can be combined with other map elements, such as the above symbology representing tree and landcover types for Yellowstone National Park, to provide the viewer with more information. In this case, the landcover layer is set to a transparency of 30% to allow the hillshade layer to be seen. This gives the viewer an understanding of the relationship between landcover, topography, and elevation that would not be possible if one used hillshade or landcover alone.
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