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Full catalog/PACE_OCI_L3M_IOP_NRT
PACE_OCI_L3M_IOP_NRT·v3.1·dataset

How ocean water absorbs light, near real-time (PACE OCI)

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

What it measures. Per-pixel ocean optical properties that describe how seawater and what's in it absorb and scatter light, including total absorption, backscattering, light-penetration depth, and a phytoplankton-specific absorption term.

How it's made. Retrieved quickly (near real-time) from reflectance measured by the OCI instrument on NASA's PACE satellite, run through a standard optical-properties model, so calibration is rougher than the final product.

How & where you'd use it. Supports judging water clarity and type, biogeochemical studies, and cross-sensor comparisons of ocean color.

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

results = earthaccess.search_data(
    short_name="PACE_OCI_L3M_IOP_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.