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Full catalog/MODIST_L2_OC
MODIST_L2_OC·v2022.0·dataset

Ocean color and tiny plant life (Terra MODIS)

Terra MODIS Level-2 Regional 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 revealing chlorophyll from phytoplankton, water clarity, and how sunlight interacts with the upper ocean, along with related carbon and aerosol measures.

How it's made. Captured by the MODIS instrument on NASA's Terra satellite and corrected to remove the atmosphere's effects, leaving the ocean's true optical signal.

How & where you'd use it. Useful for studying ocean plant life, light penetration, primary productivity, and the ocean's role in carbon cycling.

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 span2000-02-24 → ongoing
  • Measured byTerra (MODIS)
  • 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. 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_869 - Aerosol optical thickness at 869 nm - ipar - Instantaneous Photosynthetically Available Radiation (einstein m⁻² s⁻¹) - nflh - Normalized Fluorescence Line Height (W m⁻² um⁻¹ sr⁻¹) - par - Photosynthetically Available Radiation, R. Frouin (einstein m⁻² day⁻¹) - pic - Calcite Concentration, Balch and Gordon (mol m⁻³) - poc - Particulate Organic Carbon, D. Stramski, 2007 (443/555 version) (mg m⁻³)

Get the data

modist_l2_oc_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="MODIST_L2_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.