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Full catalog/PACE_OCI_L3M_FLH
PACE_OCI_L3M_FLH·v3.1·dataset

Glow from ocean plants under stress (PACE OCI)

PACE OCI Level-3 Global Mapped Fluorescence Line Height (FLH) 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 that ocean phytoplankton give off, measured as the height of that glow above a baseline. Stronger glow often signals active or stressed blooms.

How it's made. Produced from the OCI instrument on NASA's PACE satellite, gridded into a global map; it isolates the fluorescence signal near 678–683 nm from the light leaving the water.

How & where you'd use it. Used to detect and track harmful algal blooms, find productive waters, and gauge the health and physiology of phytoplankton, with more uncertainty in murky coastal 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 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_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="PACE_OCI_L3M_FLH",
    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.