Module 6 - Georefferencing

 

Map portraying the FWC conservation easements for the bald eagle's next on the UWF campus.
Inset maps for easier observation of easements and the location of the nest in the state of Florida provided.

Module 6! What a blast! This module was by far the most comprehensive and relatable module. Real life application was utmost in this lab. 

Georeferencing is the art of assigning geographic location to a raster data set, i.e. an arial picture.

As one might assume, differences in image size, distortion, etc., could make the process quite challenging. 

Using a vector polygon layer of UWF buildings with a known coordinate system, we were able to use georeferencing tools to align or superimpose the raster dataset to the polygons and thus assign a projected coordinate system. It takes trial and error, zooming in an out of images to get points to align; but overall, once you get a good number of controls points with a low total root mean square error value, you will have aligned your image as closely as possible to their actual points on earth. 

We were able to experiment with the difference in transformation orders, and how overall appearance, not just a low RMS value, means higher map accuracy; higher order transformations allow for more bending of the raster data. 

We proceeded to georefference a real-life parcel survey, where the image had no building references, and we had to use other cues and reference points to align. This was trickier than the first two digital images as proportions were completely different and the lack of buildings as references was a roadblock. This is similar to how a real-life parcel developer would draw out plans and superimpose them over existing landscape when creating their development proposal. 

Furthermore, we used the editing tools do create vector features, a building, and a road features, as one would do when planning development in an area or denoting features. 

Lastly, we took this all full-circle and used our buffer tools to denote the bald eagle's nest in reference the UWF campus and the conservation easements zones established by the Florida Wildlife Commission to ensure their nest was protected. We even hyperlinked an image of the nest to our eagle's nest point feature attributes so that the end user could retrieve a picture!

After solving problems, ensuring eagles were protected, and relating images to their earthly coordinates, it was a good interactive week to gain more real-life skills in GIS!