The NO2 dataset provided by S5P-PAL is a reprocessing of the official NO2 data product using the official NO2 L2 processor. This dataset is dedicated to support research on the impact of the COVID lockdown on air quality from space.

This dataset has been generated due to a switch in the processor version of the NO2 processor during early December 2020 introducing a discontinuity in the time series of the Sentinel-5P NO2 data. To harmonize this data record the latest operational processor (version 02.03.01) was used to reprocess the data from the beginning of the mission until mid November 2021 (aligning with the operational deployment of the V02.03.01 processor). The reprocessing consisted of a regeneration of the FRESCO and AAI input products, followed by a reprocessing of the NO2 product itself using these new inputs. Only the final NO2 products are made available via the S5P-PAL data portal.

In order to distinguish the reprocessed products from the operational products, all products generated with PAL use PAL_ for the file class, as can be found in the filename of each product.

Note that this reprocessing activity is independent of the full mission reprocessing that is planned for 2022, which will use a new radiance calibrated L1b dataset and will be performed by the Sentinel-5P PDGS.

Information about NO2

The NL-L2 NO2 processor is developed and maintained by KNMI.

All users are encouraged to first look at the README file before downloading the data.
Further documentation about the NO2 processor and product quality can be found at the official Products and Algorithms documentation website of Sentinel-5P.
Maps are available on the Sentinel-5P Mapping Portal which has been updated to include the results of this reprocessed dataset.

Processor version history

  • v02.03.01 (2021-12-01)
    • Initial public release

Known issues

The dataset does not provide a full timeline and products for several orbits are known to be missing. Information about known acquisition gaps in the data can be found on the Mission Status webpage of Sentinel-5P.

In addition to those cases there are gaps due to missing L1b data (as can be found at the Sentinel-5P Pre-Operations Data Hub) for the following orbits: 6623, 6714, 6890, 7232, 7234, 7236, 8561, 14426.

For orbits 11266-11268 no data was available due to a processor issue.

Interactive product browsing and download

Available product files can be selected and downloaded using the SpatioTemporal Asset Catalog (STAC) browser interface.

This browser interface does not currently support the more advanced search queries made possible by the STAC API. For that you will need to programmatically query the S5P-PAL STAC endpoint.


This service is provided as part of the Sentinel-5P Product Algorithm Laboratory (S5P-PAL) and contains modified Copernicus Sentinel data processed by S[&]T.

Questions regarding this service can be send to the ESA EO Support Helpdesk.