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Full catalog/PACE_OCI_L2_CLOUD_NRT
PACE_OCI_L2_CLOUD_NRT·v3.1·dataset

Cloud thickness and droplet properties (PACE, near real-time)

PACE OCI Level-2 Regional Cloud Optical Properties - Near Real-time (NRT) Data, version 3.1
land NASA OB_CLOUD Level 2 active netCDF-4
In plain English

What it measures. Describes cloud properties pixel by pixel, including how thick clouds are, the size of their droplets or ice particles, cloud-top height, pressure, and temperature, and whether clouds are made of water or ice.

How it's made. Produced from the OCI instrument on NASA's PACE satellite as a fast near-real-time product, using readily available supporting data rather than the most refined inputs.

How & where you'd use it. Used to screen clouds when correcting ocean-color images, study how clouds interact with sunlight, and pair cloud data with ocean measurements; speed is favored over final accuracy here.

What's measured

Spectral/Engineering › Visible WavelengthsATMOSPHERE › CLOUDSATMOSPHERE › CLOUDS › CLOUD PROPERTIESATMOSPHERE › CLOUDS › CLOUD MICROPHYSICSATMOSPHERE › CLOUDS › CLOUD MICROPHYSICS › CLOUD OPTICAL DEPTH/THICKNESS

Coverage & cadence

  • Time span2024-03-05 → ongoing
  • Measured byPACE (OCI)
  • Processing levelLevel 2
  • 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. The CLOUD data suite provides per-pixel microphysics and macrophysics to support cloud/climate applications. Typical uses: screening clouds for atmospheric correction, evaluating cloud–radiation interactions, and joint analyses with ocean-color variables (e.g., chlorophyll, Rrs). Core geophysical variables in this suite include: - cloud_fraction — Cloud fraction (unitless; 0–1) - ice_cloud — Ice cloud fraction (unitless; 0–1) - water_cloud — Water cloud fraction (unitless; 0–1) - cer_16 / cer_21 / cer_22 — Cloud particle effective radius (µm) retrieved from two-channel methods using near-IR bands (1.6, 2.1, or 2.2 µm) paired with a non-absorbing band - cot_16 / cot_21 / cot_22 — Cloud optical thickness (unitless) retrieved from two-channel methods using near-IR bands - cwp_16 / cwp_21 / cwp_22 — Cloud water path (g m⁻²) retrieved from two-channel methods using near-IR bands - cth — Cloud top height (m) - ctp — Cloud top pressure (hPa) - ctt — Cloud top temperature (K) ARRAY(0x55e8f4378560)

Get the data

pace_oci_l2_cloud_nrt_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="PACE_OCI_L2_CLOUD_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.