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Full catalog/PACE_HARP2_L3M_CLOUD_GPC
PACE_HARP2_L3M_CLOUD_GPC·v3.0·dataset

What clouds are made of, mapped (PACE HARP2)

PACE HARP2 Level-3 Global Mapped Cloud Optical Properties, GISS Polarimetric Cloud (GPC) Algorithm Data, version 3.0
atmosphere NASA OB_CLOUD Level 3 active netCDF-4
In plain English

What it measures. Global maps of what clouds are made of, including the size of cloud water droplets and other properties teased out from how clouds polarize light.

How it's made. Derived from the HARP2 polarimeter on the PACE satellite using a specialized cloud algorithm, mapped onto a global grid, with some variables still experimental.

How & where you'd use it. Helps scientists understand cloud composition and behavior, which matters for weather and climate; note some fields are early and may change as the method matures.

What's measured

Atmosphere › Clouds

Coverage & cadence

  • Time span2024-02-05 → ongoing
  • Measured byPACE (HARP2)
  • Processing levelLevel 3
  • Spatial extent-180, -90, 180, 90
  • FormatsnetCDF-4
  • StatusACTIVE

What you can do with it

  • Map air pollutants — NO₂, aerosols, ozone
  • Track greenhouse gases and Earth's energy budget
  • Feed weather and air-quality analysis
Official description

The CLOUD_GPC suite provides cloud properties derived from the GISS Polarimetric Cloud (GPC) algorithm, along with additional variables obtained through combination with the OCI CLOUD suite. Given the novelty of implementing a polarimetric algorithm on a global scale, note that several experimental variables—particularly those intended for diagnostic purposes and future refinement—are included and may change in subsequent, more mature versions. Core geophysical variables in this suite include: - cloud_bow_droplet_effective_radius - Cloud droplet effective radius from Cloud Bow polarimetric retrievals using parametric fitting technique (µm) - cloud_bow_droplet_effective_variance - Cloud droplet effective variance from Cloud Bow polarimetric retrievals using parametric fitting technique (unitless) - cloud_bow_fit_correlation - Parametric fitting correlation for Cloud Bow retrievals of droplet radius and variance (unitless) - cloud_bow_rms - Root-mean-square error for Cloud Bow retrievals of droplet radius and variance (unitless) - cloud_liquid_index - Index measuring the strength of the primary rainbow in polarized reflectances from liquid cloud droplets (unitless) - cloud_rft_mode_fraction_0 - Fractional contribution of droplet mode 1 from Rainbow Fourier Transform retrievals (unitless; range: 0–1) - cloud_rft_mode_fraction_1 - Fractional contribution of droplet mode 1 from Rainbow Fourier Transform retrievals (unitless; 0–1)

Get the data

pace_harp2_l3m_cloud_gpc_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="PACE_HARP2_L3M_CLOUD_GPC",
    version="3.0",
    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.