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Full catalog/MERIS_L3m_RRS
MERIS_L3m_RRS·v2022.0·dataset

Color of light leaving the ocean (ENVISAT MERIS)

ENVISAT MERIS Level-3 Global Mapped Remote-Sensing Reflectance (RRS) Data, version 2022.0
ocean NASA OB_CLOUD Level 3 netCDF-4
In plain English

What it measures. The color of light leaving the ocean at specific wavelengths, expressed as the ratio of light coming up out of the water to the sunlight shining down on it. Different wavelength bands are stored separately.

How it's made. Derived from the MERIS instrument on the ENVISAT satellite and mapped into a global gridded product.

How & where you'd use it. A foundational ocean-color measurement used to retrieve things like chlorophyll, water clarity, and water quality, and to develop and validate other algorithms; results are less reliable in murky coastal waters.

What's measured

Oceans › Ocean Optics › Reflectance

Coverage & cadence

  • Time span2002-03-21 → 2012-05-09
  • Measured byENVISAT (MERIS)
  • Processing levelLevel 3
  • Spatial extent-180, -90, 180, 90
  • FormatsnetCDF-4
  • StatusCOMPLETE

What you can do with it

  • Watch sea-surface temperature and marine heatwaves
  • Spot algal blooms and ocean-colour shifts
  • Support fisheries and coastal monitoring
Official description

The Remote Sensing Reflectance (RRS) suite provides the remote sensing reflectance at wavelength λ (nm)—the ratio of water-leaving radiance to downwelling irradiance just above the surface (units sr⁻¹). Variables are named by their band center (e.g., Rrs_412, Rrs_443). Rrs_λ is the foundational observable used to retrieve products such as chlor_a, Kd_490, IOPs, and to support algorithm development, validation, water-quality, and ecosystem applications. Users should review per-file quality flags (e.g., land, cloud, sun glint, high aerosol) and mission documentation—especially in optically complex coastal/inland waters. Geophysical variables in this suite include: - Rrs — Remote sensing reflectance (sr⁻¹)

Get the data

meris_l3m_rrs_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="MERIS_L3m_RRS",
    version="2022.0",
    bounding_box=(-122.5, 37.2, -121.8, 37.9),  # your area (W,S,E,N)
    temporal=("2024-01-01", "2024-12-31"),       # your dates
)
files = earthaccess.open(results)   # stream straight from OB_CLOUD
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.