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Full catalog/PACE_HARP2_L2_MAPOL_OCEAN_NRT
PACE_HARP2_L2_MAPOL_OCEAN_NRT·v3.0·dataset

Haze and smoke particles over ocean, live (PACE HARP2)

PACE HARP2 Level-2 Regional Aerosol Over Ocean Optical Properties, FastMAPOL Algorithm - Near Real-time (NRT) Data, version 3.0
atmosphere NASA OB_CLOUD Level 2 active netCDF-4
In plain English

What it measures. Over the ocean, reports airborne particle properties (how much haze or smoke, particle size, and light absorption) and at the same time ocean-color quantities like water reflectance and chlorophyll, a measure of phytoplankton.

How it's made. Produced quickly from the HARP2 multi-angle polarimeter on NASA's PACE satellite using the FastMAPOL method, which is sped up with neural networks, in a near-real-time mode with less-than-ideal calibration.

How & where you'd use it. Intended for advanced aerosol and ocean-color research and for comparing results across sensors and methods, with the near-real-time caveats in mind.

What's measured

Atmosphere › Aerosols › Aerosol Particle PropertiesOCEANS › OCEAN OPTICS › OCEAN COLOROCEANS › OCEAN OPTICS › REFLECTANCEATMOSPHERE › AEROSOLS › AEROSOL OPTICAL DEPTH/THICKNESSOCEANS › OCEAN OPTICS › CHLOROPHYLL › CHLOROPHYLL CONCENTRATION

Coverage & cadence

  • Time span2024-02-05 → ongoing
  • Measured byPACE (HARP2)
  • 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. MAPOL_OCEAN provides simultaneous aerosol and ocean color products using the Fast Multi-Angle Polarimetric Ocean and Land algorithm (FastMAPOL). The retrievals jointly solve for aerosol and ocean parameters with a coupled atmosphere and ocean vector radiative-transfer model, accelerated by deep neural networks to improve speed and accuracy. The retrieved aerosol properties are then used to derive angular water leaving signals through multi-angle atmospheric corrections. Use these products for advanced aerosol and ocean color studies, cross-sensor and cross-algorithm data product analysis. Core geophysical variables in this suite include: - Rrs1/Rrs2 — Angular remote sensing reflectance before and after BRDF correction (sr⁻¹) - chla_mapol — Chlorophyll-a concentration (mg m⁻³) - aot / aot_fine / aot_coarse — Aerosol optical thickness for total/fine/coarse mode (unitless) - ssa / ssa_fine / ssa_coarse — Aerosol single scattering albedo for total/fine/coarse mode (unitless) - fmf / fvf — Aerosol fine mode fraction and fine mode volume fraction (unitless) - angstrom — Aerosol Ångström exponent (unitless; reported for 440–670 nm and 440–870 nm) - alh — Aerosol layer height (km) - reff_fine / reff_coarse — Aerosol effective radius for fine/coarse mode (µm) - veff_fine / veff_coarse — Aerosol effective variance for fine/coarse mode (unitless) - sph / sph_fine / sph_coarse — Aerosol spherical fraction for total/fine/coarse mode (unitless) - mr / mi — Real and imaginary parts of aerosol refractive index (unitless; total/fine/coarse modes available) - vd — Aerosol volume density (µm³ µm⁻²; fine/coarse modes and submodes also available) - wind_speed — Ocean surface wind speed (m s⁻¹)

Get the data

pace_harp2_l2_mapol_ocean_nrt_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="PACE_HARP2_L2_MAPOL_OCEAN_NRT",
    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.