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Full catalog/PACE_OCI_L2_AER_UAA_NRT
PACE_OCI_L2_AER_UAA_NRT·v3.1·dataset

Haze and smoke particle properties, live (PACE)

PACE OCI Level-2 Regional Aerosol Optical Properties, Unified Aerosol Algorithm (UAA) Algorithm - Near Real-time (NRT) Data, version 3.1
atmosphere NASA OB_CLOUD Level 2 active netCDF-4
In plain English

What it measures. Describes the tiny airborne particles known as aerosols (think haze, dust, and smoke): how much is in the air, how big the particles are, and how strongly they soak up light. It also reports an aerosol layer height and some basic cloud information.

How it's made. Produced quickly from the OCI sensor on NASA's PACE satellite, using a method called the Unified Aerosol Algorithm, in a near-real-time mode where speed is favored over the best-possible calibration.

How & where you'd use it. Helpful for air-quality and climate work, spotting smoke and haze events, and cleaning up ocean-color images. Because it is the fast near-real-time version, the inputs are less than ideal, so users should lean on the quality flags.

What's measured

ATMOSPHERE › AEROSOLS › AEROSOL OPTICAL DEPTH/THICKNESSATMOSPHERE › AEROSOLS › AEROSOL OPTICAL DEPTH/THICKNESS › UV AEROSOL INDEX

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

  • Map air pollutants — NO₂, aerosols, ozone
  • Track greenhouse gases and Earth's energy budget
  • Feed weather and air-quality analysis
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 AER_UAA suite provides aerosol optical properties (AOP), retrieved using the Unified Aerosol Algorithm (UAA). Core variables include measures that describe aerosol loading, size partitioning, and absorption. A companion product in the same family provides the UV Absorbing Aerosol Index (UVAI_UAA). Typical uses include air-quality and climate analyses, aerosol context for ocean-color atmospheric correction, trend studies, and model evaluation; users should refer to per-file metadata/flags for quality screening and wavelength availability. Core geophysical variables in this suite include: - Aerosol_Optical_Depth — Aerosol optical depth at multiple wavelengths (unitless) - AAOD — Average aerosol optical depth (unitless) - AerosolLayerHeight — Aerosol layer height (km) - AerosolSingleScattAlbedo — Aerosol single scattering albedo (unitless) - NUV_AerosolIndex — Near-UV aerosol index (unitless) - CloudOpticalDepth — Cloud optical depth (unitless) - CloudFraction — Radiative/derived cloud fraction (unitless; 0–1) - l2_flags — Level-2 Processing Flags (bitmask)

Get the data

pace_oci_l2_aer_uaa_nrt_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="PACE_OCI_L2_AER_UAA_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.