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Full catalog/S5P_L2__AER_AI
S5P_L2__AER_AI·v1·dataset

Index of haze and smoke in the air (TROPOMI)

Sentinel-5P TROPOMI Aerosol Index 1-Orbit L2 7km x 3.5km V1 (S5P_L2__AER_AI) at GES DISC
atmosphere NASA GES_DISC Level 2
In plain English

What it measures. A single number per location, the UV Aerosol Index, that flags the presence of light-absorbing haze and smoke such as wildfire plumes and dust in the air.

How it's made. Calculated from the TROPOMI spectrometer on the European Sentinel-5P satellite by comparing the measured ultraviolet light to what a clean, particle-free atmosphere would produce.

How & where you'd use it. Handy for quickly spotting and tracking smoke and dust events across regions, and as context for air-quality and atmospheric studies.

What's measured

ATMOSPHERE › AEROSOLS

Coverage & cadence

  • Time span2018-06-28 → 2019-08-06
  • Measured bySentinel-5P (TROPOMI)
  • Processing levelLevel 2
  • Spatial extent-180, -90, 180, 90
  • StatusCOMPLETE

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

Starting from August 6th in 2019, Sentinel-5P TROPOMI along-track high spatial resolution (~5.5km at nadir) has been implemented. For data after August 6th of 2019, please check S5P_L2__AER_AI data collection. The Copernicus Sentinel-5 Precursor (Sentinel-5P or S5P) satellite mission is one of the European Space Agency's (ESA) new mission family - Sentinels, and it is a joint initiative between the Kingdom of the Netherlands and the ESA. The sole payload on Sentinel-5P is the TROPOspheric Monitoring Instrument (TROPOMI), which is a nadir-viewing 108 degree Field-of-View push-broom grating hyperspectral spectrometer, covering the wavelength of ultraviolet-visible (UV-VIS, 270nm to 495nm), near infrared (NIR, 675nm to 775nm), and shortwave infrared (SWIR, 2305nm-2385nm). Sentinel-5P is the first of the Atmospheric Composition Sentinels and is expected to provide measurements of ozone, NO2, SO2, CH4, CO, formaldehyde, aerosols and cloud at high spatial, temporal and spectral resolutions. The TROPOMI UV Aerosol Index has been calculated based on wavelength dependent changes in Rayleigh scattering in the UV spectral range where ozone absorption is weak. A residual value is calculated from measured top-of-atmosphere (TOA) reflectance and per-calculated theoretical reflectance for a Rayleigh scattering-only atmosphere given a wavelength pair. TROPOMI UVAI products use the classical wavelength pair of 340/380 nm, and the OMI chosen 354/388 nm pair for the long-term continuous AI record. Figure 1 shows TROPOMI UVAI of orbit# 4060.

Get the data

s5p_l2__aer_ai_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="S5P_L2__AER_AI",
    version="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 GES_DISC
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.