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Full catalog/OLCIS3A_L2_EFR_OC_NRT
OLCIS3A_L2_EFR_OC_NRT·v2022.0·dataset

Ocean color and plant life, fast delivery (Sentinel-3A, near real-time)

Sentinel-3A OLCI Level-2 Regional Earth-observation Full Resolution (EFR) Ocean Color (OC) - Near Real-time Data, version 2022.0
ocean NASA OB_CLOUD Level 2 active netCDF-4
In plain English

What it measures. Provides ocean color measurements and related quantities such as chlorophyll concentration, how clear the water is, and how light penetrates the sea surface. Chlorophyll levels indicate how much microscopic plant life is present.

How it's made. Produced from the OLCI instrument on Europe's Sentinel-3A satellite as a fast, near-real-time product, using readily available supporting data rather than the most refined inputs.

How & where you'd use it. Used to monitor ocean plant life, water clarity, and coastal conditions quickly; because it is near-real-time, accuracy is somewhat traded for speed.

What's measured

Oceans › Ocean Optics › Ocean ColorOceans › Ocean Optics › ReflectanceAtmosphere › Aerosols › Aerosol Optical Depth/ThicknessAtmosphere › Aerosols › Aerosol Optical Depth/Thickness › Angstrom ExponentOceans › Ocean Optics › Chlorophyll › Chlorophyll ConcentrationOceans › Ocean Optics › Attenuation/TransmissionOceans › Ocean Chemistry › Organic CarbonOceans › Ocean Chemistry › Inorganic CarbonOceans › Ocean Optics › FluorescenceOceans › Ocean Optics › Photosynthetically Active Radiation

Coverage & cadence

  • Time span2016-04-05 → ongoing
  • Measured bySentinel-3A (OLCI)
  • Processing levelLevel 2
  • 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 Ocean Color (OC) data suite provides calibrated, atmospherically corrected ocean-optics measurements and derived biogeophysical products. This data suite includes the Apparent Optical Properties (AOP) and provides satellite-derived measures of the interaction between solar radiation and the upper ocean. AOPs are "apparent" because they depend not only on the inherent optical properties (IOPs) of seawater and its constituents but also on the ambient light field. These variables are critical for studying light penetration, primary productivity, and biogeochemical cycling. This activity was informed by the Satellite Needs Working Group (SNWG), an interagency effort of the U.S. Government dedicated to identifying and addressing Earth observation needs across U.S. civilian federal agencies. Geophysical variables in this suite include: - Kd_490 - Diffuse attenuation coefficient at 490 nm, KD2 algorithm (m⁻¹) - Rrs - Remote sensing reflectance (sr⁻¹) - angstrom - Aerosol Angstrom exponent, 443 to 865 nm - chlor_a - Chlorophyll Concentration, OCI Algorithm (mg m⁻³) - l2_flags - Level-2 Processing Flags - aot_865 - Aerosol optical thickness at 865 nm

Get the data

olcis3a_l2_efr_oc_nrt_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="OLCIS3A_L2_EFR_OC_NRT",
    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.