Surface water mapping using Sentinel-1 and Google Earth Engine

Workflow using the Google Earth Engine Code Editor

Check data availability for date range and region of interest using check_data_availability.js
Get water classification threshold (Otsu's method) using get_water_classification_threshold.js
Map surface water (using previously found threshold) using map_surface_water.js

Open surface_water_mapping.ipynb in Google Colab
Define date range and region of interest (set other parameters, too)
Use water classification threshold from above
Explore water classification
Export polygons in shapefile format to Google Drive
Once export is finished, combine shapefiles into one final shapefile (also repair invalid geometries)

Sentinel-1A was launched in April 2014 but Sentinel-1B only in April 2016.
In general, each satellite has a 12-day revisit orbit, which makes a 6-day revisit orbit when they're combined.
Sentinel-1B has been broken since December 2021 - as a consequence, there's not only less coverage since then but the observation plan has also been changed.
This tutorial includes a very useful script to be used in the Google Earth Engine Code Editor to check the availability of data for specific countries and regions according to the actual and planned operations in the observation scenario plan.

Name		Name	Last commit message	Last commit date
README.md		README.md
check_data_availability.js		check_data_availability.js
get_water_classification_threshold.js		get_water_classification_threshold.js
map_surface_water.js		map_surface_water.js
moremi_game_reserve_2016_04_22.gif		moremi_game_reserve_2016_04_22.gif
surface_water_mapping.ipynb		surface_water_mapping.ipynb