# Generated by scripts/sync_indices.py from Awesome Spectral Indices (MIT).
# DO NOT EDIT BY HAND. Edit overlays (_asi_*.yaml, _folia_*.yaml) and re-run.
# Spec: docs/spec/SPECTRAL_INDICES.md
slug: mndwi
name: Modified Normalized Difference Water Index
short_name: MNDWI
formula: (G - S1) / (G + S1)
bands:
- G
- S1
domain: water
theme: hydrology
concepts:
- river-discharge
rank: 6
display:
  colormap: brbg
  range:
  - -1.0
  - 1.0
pedagogy:
  description: 'Modified Normalized Difference Water Index (Xu 2006). Replaces NDWI''s

    near-infrared term with shortwave-infrared band 1, sharpening the

    water-versus-built contrast that NDWI confuses. The surface-water

    masking standard in urban and shadowed scenes.

    '
  use_cases:
  - Urban surface-water mapping where buildings and shadow contaminate NDWI
  - Reservoir and lake extent change over multi-year archives
  - Pre-processing mask for in-water chlorophyll (NDCI) and turbidity workflows
  limitations:
  - Mountain shadow can still register as water in steep terrain — AWEInsh corrects this further
  - Requires a SWIR band; not computable on RGB-N sensors (Planet Dove classic, drones)
  - Mixed pixels at narrow water boundaries are still ambiguous
  interpretation:
    high: Open water
    mid: Wet soil, mixed-water pixels
    low: Vegetation, soil
    negative: Built-up surfaces
  authoritative_sources:
  - label: Xu 2006
    url: https://doi.org/10.1080/01431160600589179
  - label: NV5 ENVI — Water Features
    url: https://www.nv5geospatialsoftware.com/docs/AlphabeticalListIndices.html
  - label: Index Database · MNDWI
    url: https://www.indexdatabase.de/db/i-single.php?id=633
references:
- url: https://doi.org/10.1080/01431160600589179
date_of_addition: '2021-04-07'
contributor: https://github.com/davemlz
platforms:
- Sentinel-2
- Landsat-OLI
- Landsat-TM
- Landsat-ETM+
- MODIS
source:
  authority: awesome-spectral-indices
  commit_sha: 7f28d3fe68af1287f7449faf0685659e73197212
  upstream_id: MNDWI
match_tags:
- difference
- g
- index
- modified
- normalized
- s1
- water
status: stable