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Full catalog/PACE_OCI_L3M_FLH_NRT
PACE_OCI_L3M_FLH_NRT·v3.1·dataset

Glow from ocean plant life (PACE, near-real-time)

PACE OCI Level-3 Global Mapped Fluorescence Line Height (FLH) - 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 the faint red glow given off by ocean phytoplankton (chlorophyll fluorescence near 678-683 nm), measured as fluorescence line height — essentially how much the plant glow rises above the background. Higher values often mark active blooms.

How it's made. Produced quickly (near-real-time) from the OCI instrument on the PACE satellite, computed as the height of the measured signal above an interpolated baseline; near-real-time means it uses best-available rather than final calibration.

How & where you'd use it. Used to detect and track harmful algal blooms, spot productive waters, and gauge phytoplankton health; accuracy drops in murky coastal or inland waters.

What's measured

Oceans › Ocean Optics › FluorescenceBIOSPHERE › ECOSYSTEMS › AQUATIC ECOSYSTEMSBIOSPHERE › VEGETATION › SOLAR INDUCED FLUORESCENCEBIOSPHERE › ECOSYSTEMS › AQUATIC ECOSYSTEMS › PLANKTON › PHYTOPLANKTON

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 Fluorescence Line Height (FLH) data suite quantifies the red chlorophyll-a fluorescence (~678–683 nm) emitted by phytoplankton, computed as the height of the measured water-leaving radiance above a spectrally interpolated baseline. FLH is widely used for HAB detection and tracking, identifying productive waters, and assessing phytoplankton physiology; values tend to be elevated in active blooms and can be reduced in complex waters. As with all ocean-color products, uncertainties increase in optically complex coastal/inland waters, so users should refer to mission/algorithm notes for details. Geophysical variables in this suite include: - nflh — Normalized Fluorescence Line Height (W m⁻² µm⁻¹ sr⁻¹)

Get the data

pace_oci_l3m_flh_nrt_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="PACE_OCI_L3M_FLH_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.