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Full catalog/PACE_OCI_L3B_KD
PACE_OCI_L3B_KD·v3.1·dataset

How deep light reaches into the ocean (PACE)

PACE OCI Level-3 Global Binned Diffuse Attenuation Coefficient of Downwelling Irradiance (KD) Data, version 3.1
ocean NASA OB_CLOUD Level 3 active netCDF-4
In plain English

What it measures. How quickly sunlight fades as it sinks into the ocean, measured per location. Lower values mean clearer water where light reaches deeper; higher values mean murkier water.

How it's made. Derived from the PACE satellite's ocean-color instrument using an established optical model, then binned into a global gridded product.

How & where you'd use it. Used to estimate how deep the sunlit zone goes, track coastal water clarity and turbidity, interpret algae blooms, and feed ocean ecosystem models. Readings are less reliable in murky coastal or inland waters.

What's measured

Oceans › Ocean Optics › Attenuation/Transmission

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 spectral diffuse attenuation coefficient of downwelling irradiance (Kd). Kd is an apparent optical property (AOP) that is derived from IOPs using the Lee bio-optical model. Kd describes how visible light diminishes with depth in the ocean. Lower values indicate clearer water (deeper light penetration); users commonly apply Kd to estimate euphotic depth, track coastal water quality and turbidity, interpret bloom/light environments, and supply inputs to biogeochemical and ecosystem models. As with all ocean-color products, uncertainties can be larger in optically complex coastal or inland waters; refer to the file metadata and algorithm documentation for quality flags and usage notes. Geophysical variables in this suite include: - Kd — Diffuse attenuation coefficient of downwelling irradiance, Lee algorithm (m⁻¹)

Get the data

pace_oci_l3b_kd_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="PACE_OCI_L3B_KD",
    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.