Earth Data School
About
Full catalog/OLCIS3A_L2_ERR_OC
OLCIS3A_L2_ERR_OC·v2022.0·dataset

Ocean color and tiny sea plants (Sentinel-3A, reduced res)

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

What it measures. Ocean color readings that capture how sunlight interacts with the upper layers of the sea, including chlorophyll concentration (a stand-in for tiny floating plants called phytoplankton), water clarity, and how reflective the surface is at different colors. It also reports haziness from airborne particles over the ocean.

How it's made. Built from light measurements by the OLCI instrument on Europe's Sentinel-3A satellite, then cleaned up for atmospheric haze and turned into ocean-property products at a coarser, reduced resolution.

How & where you'd use it. Helps researchers track ocean plant life, study how light penetrates seawater, and follow the ocean's role in carbon and nutrient cycles.

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

results = earthaccess.search_data(
    short_name="OLCIS3A_L2_ERR_OC",
    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.