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Full catalog/CZCS_L3m_RRS
CZCS_L3m_RRS·v2022.0·dataset

Color of light leaving the ocean (Nimbus-7 CZCS)

Nimbus-7 CZCS 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 across several wavelengths, expressed as the ratio of light coming up out of the water to sunlight hitting the surface.

How it's made. Derived from the CZCS instrument on the Nimbus-7 satellite and delivered as global mapped images.

How & where you'd use it. This is the foundational measurement from which products like chlorophyll and water clarity are calculated; it is mainly used to build and validate those other products.

What's measured

Oceans › Ocean Optics › Reflectance

Coverage & cadence

  • Time span1978-10-30 → 1986-06-22
  • Measured byNimbus-7 (CZCS)
  • 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

czcs_l3m_rrs_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="CZCS_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.