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Full catalog/S5P_L2__AER_AI_HiR_NRT
S5P_L2__AER_AI_HiR_NRT·v2·dataset

Haze, dust and smoke in the air (Sentinel-5P, near real-time)

Sentinel-5P TROPOMI Near-Real-Time (NRT) Aerosol Index 1-Orbit L2 5.5km x 3.5km V2 (S5P_L2__AER_AI_HiR_NRT) at GES DISC
atmosphere NASA GES_DISC Level 2 active
In plain English

What it measures. Provides an aerosol index, a quick indicator of haze, dust, and smoke (especially absorbing particles like soot) in the air, at about 5.5 by 3.5 km detail.

How it's made. Derived from the TROPOMI instrument on the ESA Sentinel-5P satellite in a fast near-real-time mode, with files typically available within three hours and kept for only about ten days.

How & where you'd use it. Good for rapid tracking of smoke and dust events; for careful long-term analysis the offline version of this product is recommended instead.

What's measured

ATMOSPHERE › AEROSOLS

Coverage & cadence

  • Time span2025-01-27 → ongoing
  • Measured bySentinel-5P (TROPOMI)
  • Processing levelLevel 2
  • Spatial extent-180, -90, 180, 90
  • 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 Sentinel-5P TROPOMI Near Real Time (NRT) Aerosol Index 1-Orbit L2 5.5km x 3.5km V2 (S5P_L2__AER_AI_HiR_NRT) at GES DISC is the near real time version of the offline S5P_L2__AER_AI_HiR data product. These data are typically available within three hours of measurement as required by the Land Atmosphere NRT Capability Earth Observing System (LANCE). These data are intended for a rapid turnaround assessment and are only archived for up to ten days. Users who require a longer data record, or wish to conduct rigorous analysis should use the offline version of this product S5P_L2__AER_AI_HiR. 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. Data are stored in individual files, or granules, that contain one orbit of information. The data are stored in netCDF4 data format and files and complete files are ~20 MB.

Get the data

s5p_l2__aer_ai_hir_nrt_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="S5P_L2__AER_AI_HiR_NRT",
    version="2",
    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.