This week's lab had us perform damage assessment using aerial imagery of a Hurricane Sandy impacted study area. I had to use ArcGIS Pro's Mosaic Dataset feature in order to start comparing the pre- and post-storm imagery. The Swipe feature in the Appearance Tab was very useful in performing the assessment.
In order to determine the extent of the structural damage, I first had to create a coastline polyline feature layer using the pre-storm imagery as a guide. Then, I used the Select By Location tool to select houses within the required distances from the coastline, then I added a 1 or 0 to their respective distance fields I previously added to the Structure Damage table. In order to obtain the counts, I used the Select By Attributes tool. Structures within 100 m would be 1 / 1 / 1 / x, 200 m would be 0 / 1 / 1 / x and 300 m would be 0 / 0 / 1 / x for the Expression selections of "100m / 200m / 300m / Structure Damage" within the Attribute Table, respectively.
The structure damage counts found suggest that buildings closer to the coast have a higher probability of major damage or complete destruction (42% destroyed @ 100 m vs 13% destroyed @ 200 m vs 7% minor damage @ 300 m). This damage appears to have been primarily caused by storm surge.
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