Lab #6: DEMs in ArcGIS

In this week's lab we are looking at digital elevation models or DEMs. DEMs contain an array of elevation measurements that are usually organized as squares or rectangular grids. DEMs help highlight locations with dramatic elevation changes such as mountains, volcanoes and canyons. 

The area of interest that I selected was that of the Malibu/Ventura area. The map highlights Point Mugu which is a naval base in Ventura County shown in the lower left part of the map. The lower right area of the map features Highway 23, which is also known as Decker Canyon. Inland we have the 101 freeway which passes through agricultural land in Fillmore, Moorpark and Oxnard. Along the coast section of the map runs Pacific Coast Highway (PCH). I chose this area of interest because I have grown up camping and surfing in this area. Thus, I was interested to see what it would look like in a DEM. There are also great hiking trails and canyons as well in this area which represent the changes of elevation present in this area. 

What I found most interesting in this DEM was the contrast in elevation from that of sea level to the Santa Monica Mountains which surround the area. In the shaded relief model the blue color represents low elevation, i.e. sea level and below sea level, and the yellow and red represent increases in elevation. The red represents the Santa Monica Mountains. Furthermore, in the Slope map we see that the slope is very steep and rapidly increases. It goes from being flat (green) to being very steep (red). Lastly, the 3D image of my location helps show the increase in elevation from sea level to that of areas of high elevation, i.e. mountains. The points of highest elevation are represented in dark blue. 

All in all, I found this to be a very interesting lab exercise because Digital Elevation Models can tell us many things. For example, by looking at the elevation of certain areas we can figure out what types of flora and fauna are present in these regions based on the types of elevations that they live in. This is just one of the few things that DEMs can tell us. 

Here is some additional information about my maps:

Extent: 

top: 34.29 degrees, left: -119.15 degrees, right: -118.74 degrees, bottom: 34.03 degrees

Geographic Coordinate System:

GCS North American 1983