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Full catalog/PACE_OCI_L3M_PAR_NRT
PACE_OCI_L3M_PAR_NRT·v3.1·dataset

Sunlight available to ocean plants, near-real-time (PACE OCI)

PACE OCI Level-3 Global Mapped Photosynthetically Available Radiation (PAR) - Near Real-time (NRT) Data, version 3.1
ocean NASA OB_CLOUD Level 3 active netCDF-4
In plain English

What it measures. A global map of how much sunlight in the range plants use (400–700 nm) reaches the ocean surface each day, expressed as the amount of usable light energy for photosynthesis.

How it's made. Produced from the OCI instrument on NASA's PACE satellite and gridded globally; this near-real-time version is made quickly using best-available supporting data, so it's less refined than the standard product.

How & where you'd use it. Used to estimate ocean plant productivity, interpret phytoplankton blooms, and support ecosystem models, with the fast turnaround helping time-sensitive work.

What's measured

Oceans › Ocean Optics › Photosynthetically Active Radiation

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 Photosynthetically Available Radiation (PAR) data suite provides satellite-based estimates of the downwelling solar radiation in the 400–700 nm range that is available for photosynthesis at the ocean surface. These products quantify the daily or instantaneous amount of usable light energy, expressed in moles of photons m⁻² (commonly noted as “Einstein m⁻²”), and are widely used to estimate marine primary production, interpret phytoplankton bloom dynamics, provide context for optical and biogeochemical measurements,and support ecosystem models and education on light–biology interactions. Geophysical variables in this suite include: - par — Daily photosynthetically available radiation (mol photons m⁻² d⁻¹)

Get the data

pace_oci_l3m_par_nrt_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="PACE_OCI_L3M_PAR_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.