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Useful things we can do with a DEM

A digital elevation model (DEM) represents the spatial and altitudinal distribution through a matrix image, without focusing on its conceptualization, but in its utility, in this post we will explain some of the products that can be obtained (are requires ArcGIS Spatial Analyst license), although most of those tools includes mapping software, an important aspect is the resolution, but it all depends on our goals, without details, with a DEM can do the following:

Slope map

Imagine going to build a country house in slope map that goes from green (background) to red (very steep), we can identify the location that best suits our interests, the tool to create outstanding degrees or percentage is Slope located in:

ArcToolbox > Spatial Analyst Tools > Surface

Mapa de pendientes

Contours

Allow the representation of the terrain by a set of equally spaced planes, they can be generated at different intervals with the Contour tool, not only you can limit the creation of contour lines, but also to represent different continuous phenomena such as precipitation, temperature, radiation solar, atmospheric pressure, etc.

ArcToolbox > Spatial Analyst Tools > Surface

Curvas de nivel

Shadow map

The DEM receives a hypothetical for each cell lighting, resulting in an image showing the “relief” in ArcMap can make a shaded relief activating the Image Analysis (Windows menu), select the DEM and click Shaded Relief, you can also perform shading with the Hillshade tool located at:

  ArcGIS 10 Manual PDF

ArcToolbox > Spatial Analyst Tools > Surface

Shaded Relief

Visibility map

Identify the places that are visible from a location on the DEM, in the following image from the blue dot surfaces in green are visible, which are marked in red they are not, the tool used is Visibility located in:

ArcToolbox > Spatial Analyst Tools > Surface

Mapa de visibilidad

Aspect map

If required to find the slopes are facing north or south on a mountain, the Aspect tool allows to calculate the orientation of each surface with respect to its neighboring cells based on the downward slope.

ArcToolbox > Spatial Analyst Tools > Surface

Mapa de aspecto

Reclassify

Group values based on a common attribute, in this case have been set different altitudinal the DEM, but can reclassify any raster image, for example to group different types of vegetation cover, the Reclassify tool perform this operation.

ArcToolbox > Spatial Analyst Tools > Reclass

Reclasicar DEM

Histogram

The histogram lets you view the distribution of values for each pixel in the XY axes, also shows their statistics to better understand the variable under study.

Right click on the DEM > Properties > Symbology > Stretched > Histograms

Histograma de un DEM