bi-transect-extractor

Release Date:

Get started

Required software

ArcGIS Pro (2.0 recommended), which includes an installation of Anaconda and Python 3. The default installation creates a conda environment, arcgispro-py3 where you have access to the Python 3 version of ArcPy as well as the other ArcGIS Pro default Python programs. This installation of Anaconda is separate from any existing installations you may have.

Installation

We recommend that you install this package in the ArcGIS Pro conda environment through pip. First, activate the arcgispro-py3 conda environment: \ArcGIS\Pro\bin\Python\Scripts\proenv. Then, install this package: pip install git+https://code.usgs.gov/cmgp/bi-transect-extractor.git

The Jupyter notebook files must be run within the ArcGIS Pro conda environment. To do so, type the following in your command prompt (assuming it has the default set-up and substituting path\to\dir with the location of the repository):

cd path\to\dir\bi-transect-extractor
\ArcGIS\Pro\bin\Python\Scripts\proenv
jupyter notebook

How to implement

1. Acquire all input datasets and save them into an Esri file geodatabase.

  • National Assessment of Shoreline Change (NASC) transect lines. Long-term shoreline change rates transect file from the NASC (U.S. Geological Survey Open-File Report 2010-1119)
  • Lidar-derived beach morphology points. These are published through the USGS National Assessment of Coastal Change Hazards Beach Morphology (Dune Crest, Dune Toe, and Shoreline) for U.S. Sandy Coastlines. They need to be separated into shoreline, dune crest, and dune toe points.
  • Digital elevation model (DEM). A good source for airborne lidar datasets is NOAA's Digital Coast. The lidar dataset should be the same as that used to derive the morphology points.
  • boundary polygon <- DEM + shoreline points + inlet lines (+ manual)
  • supplemented and sorted transects <- script + manual; Sorting is only semi-automated and tricky. See explanations below/in prepper.ipynb.
  • 'tidied' extended transects <- script + manual

2. Review values (mostly file paths) in setvars.py and extractor.ipynb and update if needed.

3. QA/QC/cross-check everything thoroughly: projections, agreement, etc. Preferred projection is NAD83, Meters - Albers or UTM Zone 18N or 19N depending on region of Atlantic coast. Where projection is important, the script will reproject as necessary. You may need to create the following files:

  • inlet lines <- DEM + manual
  • armoring lines <- ortho + manual

4. extractor.ipynb.