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Full catalog/PACE_OCI_L3M_SFREFL_NRT
PACE_OCI_L3M_SFREFL_NRT·v3.1·dataset

True surface colors, near real-time (PACE)

PACE OCI Level-3 Global Mapped Surface Reflectance - Near Real-time (NRT) Data, version 3.1
land NASA OB_CLOUD Level 3 active netCDF-4
In plain English

What it measures. The true reflected colors of Earth's land surface as seen from space, measured across 122 wavelengths from visible light into the shortwave infrared, with the atmosphere's effects removed.

How it's made. Produced quickly (near real-time) from the OCI instrument on NASA's PACE satellite, mapped globally and masked for clouds, using best-available supporting data so it trades some accuracy for speed.

How & where you'd use it. A foundational input for tracking vegetation and other land products; most people use it indirectly through downstream products like vegetation indices rather than the raw reflectance itself.

What's measured

LAND SURFACE › SURFACE RADIATIVE PROPERTIES › REFLECTANCELAND SURFACE › SURFACE RADIATIVE PROPERTIES

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

  • Track deforestation, fire scars and land-cover change
  • Monitor crop and vegetation health (NDVI/EVI)
  • Map how built-up vs. green an area is over time
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. Surface Reflectance (SFREFL) provides the unitless, bottom-of-atmosphere reflectance of the Earth’s surface at 122 wavelengths (346 - 895 nm, with 5 SWIR bands). Surface Reflectance is the foundational input for downstream land products (e.g., vegetation indices included in the LANDVI suite). Users should review the documentation for more information on atmospheric correction and quality flags. Users should also note that the L3M product is masked for clouds. Geophysical variables in this suite include: - rhos – Surface reflectance (unitless)

Get the data

pace_oci_l3m_sfrefl_nrt_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="PACE_OCI_L3M_SFREFL_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.