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Sentinel-5p/TROPOMI: Mapping air quality in unprecedented detail

The launch of Sentinel-5p on 13 October 2017. (source: ESA)

Last week, on October 13, 2017, the European satellite Sentinel-5 Precursor (Sentinel-5p) was launched from the Russian Cosmodrome of Plesetsk on behalf of the European Space Agency (ESA). Its payload contains a single instrument, the TROPOspheric Monitoring Instrument (TROPOMI), that is designed to analyse the chemical composition of the Earth's atmosphere in unprecedented detail. The UV-VIS/DOAS group and other scientists from the Royal Belgian Institute for Space Aeronomy (BIRA-IASB) are strongly involved in the analysis of TROPOMI's data.

After the successful launch of several Sentinel satellites for the monitoring of land and ocean, Sentinel-5p has been developed by ESA and the Netherland Space Office (NSO) as the first atmospheric monitoring satellite of the EU Copernicus Earth Observation programme. This programme aims at the operational provision of advanced information services on our environment and security to public authorities, policy makers and the citizen. As part of Copernicus, Sentinel-5p and TROPOMI will act as precursor of the future Sentinel-5 mission to be launched in 2022.

TROPOMI will measure a wide range of different trace gases.(source: ESA)

TROPOMI will measure at the global scale and at unprecedented horizontal resolution, with the smallest ground pixels measuring only 7x3.5 km2 in size. It will monitor atmospheric composition data related to air quality, ozone and climate change issues. The outstanding performances of the TROPOMI instrument will enable more detailed than ever detection of pollution emitters at city level, of small scale atmospheric effects on regional climate change, and of aviation hazards due to volcanic eruptions. These research themes strongly overlap with the experience at BIRA-IASB.

With support from the Belgian Federal Science Policy (BELSPO) and ESA, BIRA-IASB plays a key role in the production, validation and analysis of the future Sentinel-5p data. In total, some 30 scientists from 4 different teams are involved in the analyses of the data of the TROPOMI instrument. The UV-VIS/DOAS group has developed the official algorithm for the derivation of the amounts of sulphur dioxide (SO2) and formaldehyde (HCHO), two important pollutants and precursors of climate change. BIRA-IASB further strongly contributes to the algorithm deriving total ozone columns and is also in charge of the operational quality monitoring of all Sentinel-5p atmospheric data and thereby gives precious feedback to ESA and the Copernicus services on the health of the instrument. Finally, atmospheric models will be used to analyse the implications of Sentinel-5p data in terms of pollutants emissions and atmospheric processes.


Left: TROPOMI light pathways (source: ESA); Right: TROPOMI daily coverage. (source: ESA/ATG)


Last update on 17 Oct 2017