TROPOMI utilises a single telescope to form an image of the target area onto a rectangular slit that acts as the entrance slit of the spectrometer system. There are four different spectrometers, each with its own optics and detector: mediumwave ultraviolet (UV), longwave ultraviolet combined with visible (UVIS), near infrared (NIR), and shortwave infrared (SWIR). The spectrometers for UV, UVIS and NIR are jointly referred to as UVN. Radiation for the SWIR spectrometer is transferred by an optical relay part in the UVN system from the telescope to an interface position (the pupil stop) for the SWIR spectrometer. This is done because of the more stringent thermal requirements on the SWIR part of the instrument.

There are two different types of L1B data products available to users:

  • L1B radiance products, containing Earth radiance spectra.
    There is one L1b radiance product type for each spectral band (product identifiers L1B_RA_BD1 through L1B_RA_BD8). Radiances are measured on the dayside along every orbit. See the radiance product page.
  • L1B irradiance products, containing solar irradiance spectra.
    There are two L1b irradiance product types. The first (product identifier L1B_IR_UVN) contains the solar irradiance spectra for the UVN bands (band 1 through band 6). The second (product identifier L1B_IR_SIR) contains the solar irradiance spectra for the SWIR bands (band 7 and band 8). Irradiances are measured once every 15 orbits. This page refers to the irradiance products.

More information and examples

Dataset Specifications

Examples of filenames:

S5P_OFFL_L1B_IR_UVN_20260201T131008_20260201T145139_43033_03_030000_20260201T164108.nc S5P_OFFL_L1B_IR_SIR_20260201T131008_20260201T145139_43033_03_030000_20260201T164108.nc S5P_RPRO_L1B_IR_UVN_20220701T125629_20220701T143758_24433_03_020100_20230104T141142.nc S5P_RPRO_L1B_IR_SIR_20220701T125629_20220701T143758_24433_03_020100_20230104T141142.nc

Elements in the filename separated by underscores after the initial "S5P":
* processing type: near-real time (NRTI), off-line (OFFL), reprocessing of off-line (RPRO)
* product identifier [10 char.]
* start date and time of the full orbit in which the irradiance measurement was taken
* end date and time of the full orbit
* orbit number [5 char.]
* collection number [2 char.]
* version number [6 char.]
* production date and time
In case of OFFL and RPRO contain single irradiances; near-real time (NRTI) is not defined for irradiances.

Dataset Specifications V3

Temporal Coverage

Since 27-Nov-2025

Spatial CoverageN/A
Spatial Resolution

N/A

Processor Version03.xx.xx, with x=any digit between 0 and 9

Dataset Specifications V2

Temporal Coverage

From 01-Jul-2021 to 27-Nov-2025

Spatial Coverage

N/A

Spatial Resolution

N/A

Processor Version02.xx.xx, with x=any digit between 0 and 9

Dataset Specifications V1

Temporal Coverage

From 30-Apr-2018 to 01-Jul-2021

Spatial CoverageN/A
Spatial ResolutionN/A
Processor Version01.xx.xx, with x=any digit between 0 and 9

Processing Level

Level-1B processing of S5P/TROPOMI data.

How to Access the Data

The data related to this product and to the other S5P/TROPOMI products are accessible via the  Copernicus Data Space Ecosystem (CDSE).

Dataset Citation Guidelines

Users, who, in their research, use ESA Earth Observation data that have been assigned a DOI, are asked to use it when citing the data source in their publications:

Dataset Citation Guidelines V3

Copernicus Sentinel-5P (processed by ESA), 2025, TROPOMI Level 1B Irradiance products. Version 03. European Space Agency. https://doi.org/10.57780/S5P-dfac5ad

Dataset Citation Guidelines V2

Copernicus Sentinel-5P (processed by ESA), 2021, TROPOMI Level 1B Irradiance products. Version 02. European Space Agency. https://doi.org/10.5270/S5P-mhtbru8

Dataset Citation Guidelines V1

Copernicus Sentinel-5P (processed by ESA), 2018, TROPOMI Level 1B Irradiance products. Version 01. European Space Agency.