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Full catalog/PACE_OCI_L3M_IOP
PACE_OCI_L3M_IOP·v3.1·dataset

How ocean water absorbs and scatters light (PACE)

PACE OCI Level-3 Global Mapped Ocean Color Inherent Optical Properties (OC_IOP) Data, version 3.1
ocean NASA OB_CLOUD Level 3 active netCDF-4
In plain English

What it measures. Maps of how ocean water absorbs and scatters light - properties that reveal what's in the water, such as phytoplankton and dissolved organic material. It includes things like total light absorption, backscatter, and how quickly light fades with depth.

How it's made. Calculated from the color of sunlight reflected off the ocean as seen by the OCI instrument on the PACE satellite, run through an optical model and averaged into global maps.

How & where you'd use it. Used to classify water types, gauge water clarity, study ocean biology and chemistry, and compare results across different satellites more reliably.

What's measured

OCEANS › OCEAN OPTICS › ABSORPTIONOCEANS › OCEAN OPTICS › ATTENUATION/TRANSMISSIONOCEANS › OCEAN OPTICS › GELBSTOFFOCEANS › OCEAN OPTICS › REFLECTANCEOCEANS › OCEAN OPTICS › SCATTERINGBIOSPHERE › ECOSYSTEMS › AQUATIC ECOSYSTEMS › PLANKTON › PHYTOPLANKTONTERRESTRIAL HYDROSPHERE › WATER QUALITY/WATER CHEMISTRY › WATER CHARACTERISTICS › ORGANIC MATTERTERRESTRIAL 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

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

The Inherent Optical Properties (IOP) suite provides per-pixel inherent optical properties - quantities that describe how seawater and its constituents absorb and scatter light, independent of illumination or viewing geometry. IOPs are retrieved from spectral Remote Sensing Reflectance (Rrs) using the default configuration of the Generalized Inherent Optical Properties (GIOP) model framework. These products support water-type classification, water-clarity assessment, biogeochemical studies, and forward/adjoint radiative-transfer applications, and they enable more robust cross-sensor comparisons than purely apparent (AOP) products. The hyperspctral band list is found in the science data file metadata. Geophysical variables in this suite include: - Kd - Diffuse attenuation coefficient of downwelling irradiance (m^-1) - a - Total absorption coefficient (sum of pure water + phytoplankton + CDOM/detritus, m^-1) - bb - Total backscattering coefficient (m^-1) - aph - Phytoplankton absorption coefficient (m^-1) - aph_unc_442 - Uncertainty in absorption due to phytoplankton at 442 nm (m^-1) - adg_442 - Combined CDOM + non-algal detritus absorption coefficient at 442nm (m^-1) - adg_unc_442 - Uncertainty in absorption due to gelbstoff and detrital material at 442 nm (m^-1) - bbp_442 - Particulate backscattering coefficient at 442nm (m^-1) - bbp_unc_442 - Uncertainty in particulate backscattering at 442 nm (m^-1) - rrsdiff - Fractional mean Rrs difference (reconstructed from inverted IOPs - input) (unitless)

Get the data

pace_oci_l3m_iop_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="PACE_OCI_L3M_IOP",
    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.