Full catalog/SeaWiFS_L3m_IOP
SeaWiFS_L3m_IOP·v2022.0·dataset

How ocean water absorbs and scatters light (SeaWiFS)

OrbView-2 SeaWiFS Level-3 Global Mapped Inherent Optical Properties (IOP) Data, version 2022.0
ocean NASA OB_CLOUD Level 3 netCDF-4
In plain English

What it measures. Describes how ocean water and the things in it absorb and scatter light, independent of sun angle or viewing direction, including total absorption and backscattering and the contributions from phytoplankton and dissolved matter. Mapped globally.

How it's made. Calculated from SeaWiFS reflectance measurements (OrbView-2 satellite) run through the GIOP optical model, and gridded into a global Level-3 product.

How & where you'd use it. Supports classifying water types, judging water clarity, biogeochemistry studies, and comparing data across different ocean-color sensors.

What's measured

Oceans › Ocean Optics › AbsorptionOceans › Ocean Optics › ScatteringOceans › Ocean Optics › GelbstoffBiosphere › Ecosystems › Aquatic Ecosystems › Plankton › Phytoplankton

Coverage & cadence

  • Time span1997-09-04 → 2010-12-11
  • Measured byOrbView-2 (SeaWiFS)
  • 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 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. Geophysical variables in this suite include: - a — Total absorption coefficient (sum of pure water + phytoplankton + CDOM/detritus, m⁻¹) - bb — Total backscattering coefficient (m⁻¹) - aph_443 — Phytoplankton absorption coefficient at 443 nm (m⁻¹) - aph_unc_443 — Uncertainty in absorption due to phytoplankton at 443 nm (m⁻¹) - adg_443 — Combined CDOM + non-algal detritus absorption coefficient at 443nm; accompanied by adg_s (spectral slope, units nm⁻¹). - adg_unc_443 — Uncertainty in absorption due to gelbstoff and detrital material at 443 nm (m⁻¹). - bbp_443 — Particulate backscattering coefficient at 443nm (m⁻¹); include bbp_s (power-law slope, unitless) describing spectral shape. - bbp_unc_443 — Uncertainty in particulate backscattering at 443 nm (m⁻¹). - rrsdiff — Fractional mean Rrs difference.

Get the data

seawifs_l3m_iop_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="SeaWiFS_L3m_IOP",
    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.