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Full catalog/PACE_OCI_L3M_AVW
PACE_OCI_L3M_AVW·v3.1·dataset

The ocean's overall color tone worldwide (PACE OCI)

PACE OCI Level-3 Global Mapped Apparent Visible Wavelength (AVW) Data, version 3.1
land NASA OB_CLOUD Level 3 active netCDF-4
In plain English

What it measures. A single number summarizing the overall color tone of the ocean — essentially where the 'center' of the water's color falls across the visible range. Bluer, clearer water gives lower values; greener or browner, more productive water gives higher values.

How it's made. Calculated from ocean-color readings by the OCI instrument on NASA's PACE satellite and mapped into a global grid.

How & where you'd use it. Used to classify water types, help pick the right algorithms for things like chlorophyll, and spot regional changes in the ocean over time. Results are less reliable in murky coastal and inland waters.

What's measured

SPECTRAL/ENGINEERING › VISIBLE WAVELENGTHSOCEANS › OCEAN OPTICS › OCEAN COLORTERRESTRIAL HYDROSPHERE › WATER QUALITY/WATER CHEMISTRY › WATER CHARACTERISTICS › WATER COLORTERRESTRIAL HYDROSPHERE › WATER QUALITY/WATER CHEMISTRY › WATER CHARACTERISTICS › LIGHT TRANSMISSIONEARTH SCIENCE SERVICES › ENVIRONMENTAL ADVISORIES › HYDROLOGICAL ADVISORIES › WATER QUALITYTERRESTRIAL HYDROSPHERE › SURFACE WATER

Coverage & cadence

  • Time span2024-03-05 → ongoing
  • Measured byPACE (OCI)
  • Processing levelLevel 3
  • Spatial extent-180, -90, 180, 90
  • FormatsnetCDF-4
  • StatusACTIVE

What you can do with it

  • Track deforestation, fire scars and land-cover change
  • Monitor crop and vegetation health (NDVI/EVI)
  • Map how built-up vs. green an area is over time
Official description

AVW (Apparent Visible Wavelength) quantifies the spectral “center” of ocean color by summarizing the shape of the water‐leaving reflectance spectrum (Rrs) across the visible range. Reported in nanometers (nm), AVW is lower for bluer, clearer (oligotrophic) waters and higher for greener/browner, more optically complex or productive waters influenced by phytoplankton, colored dissolved organic matter (CDOM), or suspended sediments. Users apply AVW for water-type classification, algorithm selection/blending (e.g., guiding chlorophyll retrievals), regional change detection, and as context alongside chlor_a, Kd_490, IOPs, and PAR. As with all ocean-color products, review quality flags (cloud/glint/aerosol) and note that interpretations can vary in optically complex coastal/inland waters. Geophysical variables in this suite include: - avw — Apparent Visible Wavelength (nm)

Get the data

pace_oci_l3m_avw_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="PACE_OCI_L3M_AVW",
    version="3.1",
    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.