FloodSeverityIndex

Flood index based on Gumbel distribution of annual maxima of volumetric flow.

Table of contents

• What is it?
• Version Information
• User Guide
• Requirements
• Files in this repository
• Contact
• License

What is it?

This Python routine calculates a flood severity index based on the annual maxima of volumetric flow for the period 1981-2017. The thresholds were estimated from a Gumbel distribution using the methods of L-moments. The severity is based on a 2-yr return period (medium), 5-yr return period (high), and 20-yr return period (severe).

This routine requires data from GloFAS.

Version information

• v0.0.1: Support for severity index for South Sudan and Ethiopia.

User Guide

Command line implementations:

python FloodSeverityIndex.py data thresholds bounding_box year fig

or

docker run -ti mintproject/floodseverityindex:latest bash
python FloodSeverityIndex.py data thresholds bounding_box year fig

where:

• data: Either:
  • Path to the folder containing the GloFAS data. Data should be organized in folders per year.
  • Path to single netcdf file with concatenated data for South Sudan and Ethiopia
• thresholds: path to the file containing the flood threshold from the Gumbel distribution.
• bounding_box: List of [min_lon,max_lon,min_lat,max_lat]. Note that only South Sudan and Ethiopia are currently supported. Therefore the maximum extent of the box is: [23,48,3,15]
• year: The year of interest. Should be provided as a list to support for multiple years.
• fig: whether to return a movie

Note:

• The outputs are in netcdf format. The index is a boolean corresponding to the severity of the flood:
  0: None
  1: Medium (2-yr return period)
  2: high (5-yr return period)
  3: severe (20-yr return period)

Examples: python FloodSeverityIndex.py ./ GloFAS_FloodThreshold.nc [23,48,3,15] [2016,2017] True

Requirements

Tested under Python 3.7

Package requirements:

• xarray = 0.12.1 (Do not update to the latest version)
• numpy
• cartopy
• panda
• matplotlib
• imageio

Note: To use mp4, after installing imegeio, pip install imageio-ffmpeg

Files in this directory

• FloodSeverityIndex.py: Executable
• GloFAS_FloodThreshold.nc: Files containing the thresholds

Contact

Please report issues to khider@usc.edu

License

The project is licensed under the Apache v2.0 License. Please refer to the file call license.