GIS 5935 Lab 4 - Surface TINs and DEMs

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Lab 4 of GIS 5935 involved using Triangulated Irregular Network (TIN) and Digital Elevation Model (DEM) to visualize the surface of the ground. A TIN represents the earth surface using linked irregular shaped triangles with three dimensional coordinates at each of the vertices. A DEM represents the ground as a two-dimensional raster where each grid cell has an elevation value.

The first part of the lab was to drape an aerial image on top of a TIN. Below is an image of the Furnace Creek aerial drape over the TIN that represents the earth’s surface.
















The next part of the lab was to determine suitable land for a potential ski run using a provided DEM. This involved building a suitability model that ranked land based on elevation, slope, and aspect ratio. Each dataset was reclassified based on the rankings and then merged into one feature class using a weighted overlay. The following ski run suitability map shows the results.





















Below is map of a TIN that is shaded based on elevation and also shows the contours and TIN triangles.
















The maps below show contours that were produced from the TIN and DEM. The X points marks are the original points used to create both the TIN and the DEM.







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