# 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: mcari
name: Modified Chlorophyll Absorption in Reflectance Index
short_name: MCARI
formula: ((RE1 - R) - 0.2 * (RE1 - G)) * (RE1 / R)
bands:
- RE1
- R
- G
domain: vegetation
theme: vegetation
concepts: []
rank: 19
display:
  colormap: rdylgn
  range:
  - 0.0
  - 1.5
pedagogy:
  description: 'Modified Chlorophyll Absorption in Reflectance Index (Daughtry 2000).

    A triangular formulation using green, red, and red-edge band 1 that

    isolates the chlorophyll-absorption depth at ~670 nm while minimising

    soil-background contamination.

    '
  use_cases:
  - Leaf-chlorophyll content estimation in precision-agriculture nitrogen mapping
  - Forest canopy stress detection in red-edge-equipped sensors
  - Component of two-index MCARI/MTVI2 pairs that disentangle chlorophyll from LAI
  limitations:
  - Requires a red-edge band ~705 nm (S2 RE1, MERIS B5) — not available on Landsat or MODIS
  - Sensitive to LAI — interpret jointly with a structural index (MTVI2, OSAVI) for unconfounded chlorophyll
  - Soil-line assumption affects absolute values; use over canopy with similar soil background
  interpretation:
    high: High leaf chlorophyll content
    mid: Typical canopy
    low: Low chlorophyll, stressed or sparse vegetation
  authoritative_sources:
  - label: Daughtry 2000
    url: https://doi.org/10.1016/S0034-4257(00)00113-9
  - label: NV5 ENVI — Leaf Pigments
    url: https://www.nv5geospatialsoftware.com/docs/LeafPigments.html
  - label: Index Database · MCARI
    url: https://www.indexdatabase.de/db/i-single.php?id=42
references:
- url: http://dx.doi.org/10.1016/S0034-4257(00)00113-9
date_of_addition: '2021-05-13'
contributor: https://github.com/davemlz
platforms:
- Sentinel-2
source:
  authority: awesome-spectral-indices
  commit_sha: 7f28d3fe68af1287f7449faf0685659e73197212
  upstream_id: MCARI
match_tags:
- absorption
- chlorophyll
- g
- index
- modified
- r
- re1
- reflectance
- vegetation
status: stable