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Full catalog/VIIRSJ2_L3m_PIC_NRT
VIIRSJ2_L3m_PIC_NRT·v2025.0·dataset

Chalky mineral particles in the ocean (NOAA-21, near-real-time)

NOAA-21 VIIRS Level-3 Global Mapped Particulate Inorganic Carbon (PIC) - Near Real-time (NRT) Data, version 2025.0
ocean NASA OB_CLOUD Level 3 active netCDF-4
In plain English

What it measures. The amount of chalky mineral particles (calcite, mostly from tiny shelled plankton called coccolithophores) floating in surface seawater, mapped globally. Because it's a near-real-time product, the calibration is rougher than the final version.

How it's made. Derived from ocean-color measurements by the VIIRS instrument on the NOAA-21 satellite, processed quickly into a gridded global map using an established algorithm.

How & where you'd use it. Used to spot and measure blooms of coccolithophores and to study how carbon in the form of calcite cycles through the ocean. Coastal and hazy conditions add uncertainty, so check the quality flags.

What's measured

Oceans › Ocean Chemistry › Inorganic CarbonOCEANS › OCEAN CHEMISTRY › CARBONOCEANS › OCEAN OPTICS

Coverage & cadence

  • Time span2022-11-10 → ongoing
  • Measured byNOAA-21 (VIIRS)
  • 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 Particulate Inorganic Carbon (PIC) data suite includes product of particulate inorganic carbon (calcite, typically from coccolithophores) from ocean-color reflectance using the Balch & Gordon algorithm. PIC is used to detect and quantify coccolithophore blooms, assess carbonate cycling and optical backscatter, and provide biogeochemical context alongside chlor_a, Kd_490, PAR, and SST. As with all ocean-color retrievals, uncertainties increase in optically complex coastal/inland waters or under high aerosol/glint; users should refer to per-mission algorithm notes and quality flags before analysis. Geophysical variables in this suite include: - pic — Particulate Inorganic Carbon (Calcite concentration, Balch and Gordon) (mol m⁻³)

Get the data

viirsj2_l3m_pic_nrt_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="VIIRSJ2_L3m_PIC_NRT",
    version="2025.0",
    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.