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Full catalog/PACE_OCI_L3M_AVW_NRT
PACE_OCI_L3M_AVW_NRT·v3.1·dataset

Average ocean color wavelength, near real-time (PACE)

PACE OCI Level-3 Global Mapped Apparent Visible Wavelength (AVW) - Near Real-time (NRT) 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 of ocean water, the Apparent Visible Wavelength in nanometers. Lower values mean bluer, clearer water; higher values mean greener or browner, more productive or sediment-rich water.

How it's made. Produced quickly (near real-time) from the OCI instrument on NASA's PACE satellite and mapped onto a global grid; because it's the fast version, it uses less-than-ideal calibration and supporting data.

How & where you'd use it. Helps classify water types, guide which ocean-color algorithms to apply, and spot regional changes. As with all ocean-color data, check the quality flags for clouds and glint.

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

The Ocean Biology DAAC produces near real-time (NRT) products using the best-available combination of ancillary data from meteorological and ozone data. As such, the inputs and the calibration used are less than optimal. Near real-time products provide a snapshot of the data during a short time period within a single orbit. 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_nrt_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="PACE_OCI_L3M_AVW_NRT",
    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.