TINs and DEMs

GIS 5935 Special Topics in GIS 
Lab 4

Student Learning Outcomes:

• Create 3D visualizations of elevation models
• Create and modify a TIN using various input datasets
• Compare TIN and DEM elevation models in terms of their properties 

The purpose of this lab is to become familiar with Triangulated Irregular Networks (TIN) and Digital Elevation Models (DEM). 

Part A: Draping an Image over terrain

Draping an image over terrain can lead to increased understanding. Being able to see areas in 3D is a very powerful way of representing spatial data. 

Part B: Using a DEM to Develop a Ski Run Suitability Map

Using the provided Raster image I created a TIN of the elevation. Using the Reclassify tool I created 5 new rasters (slope, aspect, and reclassification rasters for the originals elevation DEM, slope and aspect). These were then combined using weighted overlay to create a map where the higher the number the more suitable the value is. 

Part C: Exploring TINs

TINs represent the earths surface with a series of triangles as shown in the screenshot below. IN this example the colors represent different slope. Contour lines are also visible in this image. 

Part D: Creating and Analyzing TINs

In the image below TIN and DEM contours are compared for the same data set. Both datasets have contours of 100m.