In the data/ folder, make two subdirectories named in and out. Put all input data into the in directory. Output data will be stored by the script in the out directory.
This is the coastal bluff geometry dataset. It consists of 5 shapefiles, one for each state in New England. Each feature in each of the shapefiles represents the geometry of single bluff face. A bluff face is defined as the area between the "head" and "toe" of the bluff. Bluff face features in this dataset were created with a semi-automated approach. It is as follows:
STEPS: 1. Bluff locations were manually identified in a GIS using polylines placed approximately where the bluff toe would be. Identified bluffs are subject to my understanding of glacial & coastal geology and physical geography. In Maine only, there already existed a well-established dataset of bluff locations, and therefore that was used instead.
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Shore-normal transects were generated every 10 meters along bluff shorelines and elevation & mhhw values were extracted to points placed along shore-normal transects.
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Shore-normal transect points with elevation & mhhw data were fed into a bluff-geometry algorithm. Bluff geometry polygon were returned.
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Bluff geometry polygons were re-imported into a GIS and errors were manually corrected.
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Additional attributes such as slope, bluff erosion mass, and physiographic region were added.
CAVEATS: