# Ocean colour / water-leaving radiance
*methodologies*

Retrieves chlorophyll-a concentration, CDOM, and suspended sediment from spectrally resolved water-leaving radiance; good for marine primary production, harmful algal bloom detection, and coastal water quality.

## Specifications
- **family**: Multispectral
- **requirements envelope**: {"kind":"spectral","spectral_range_nm":{"min":400,"max":750},"bands_min":5,"calibration_tier_min":"reflectance","snr_min":200,"daylight_required":true,"cloud_tolerant":false}
- **entity type**: methodology
- **last verified date**: 2026-05-22
- **verified by**: sw
- **claim status**: unclaimed
- **attributes**: {"family":"Multispectral","summary":"Retrieves chlorophyll-a concentration, CDOM, and suspended sediment from spectrally resolved water-leaving radiance; good for marine primary production, harmful algal bloom detection, and coastal water quality.","requirements_envelope":"{\"kind\":\"spectral\",\"spectral_range_nm\":{\"min\":400,\"max\":750},\"bands_min\":5,\"calibration_tier_min\":\"reflectance\",\"snr_min\":200,\"daylight_required\":true,\"cloud_tolerant\":false}"}
- **technology**: optical-spectral-sensing

## Editorial
Atmospheric correction removes >90% of the top-of-atmosphere signal before water-leaving radiance is retrieved. Band-ratio empirical algorithms (OC4/OC5/OC6) or semi-analytical inversion for optically complex coastal/inland waters. [Wikipedia: Ocean color](https://en.wikipedia.org/wiki/Ocean_color)

## Sources
- [wikipedia] | Wikipedia: Ocean color | https://en.wikipedia.org/wiki/Ocean_color | tier=community | accessed=2026-05-22

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Source: https://eo-atlas.org/methodologies/ocean-colour-water-leaving-radiance
Maintainer: SpectraWorks B.V. (CC-BY 4.0)