The Boundary Layer Air Quality-Analysis Using Network of Instruments (BAQUNIN) Supersite for Atmospheric Research and Satellite Validation over Rome Area

The Boundary-layer Air Quality-analysis Using Network of Instruments (BAQUNIN) supersite is presented. The site has been collecting pollutant concentrations and meteorological parameters since 2017. Currently, BAQUNIN consists of three observation sites located in the city center of Rome (Italy), and in the neighboring semi-rural and rural areas. To the best of our knowledge, BAQUNIN is one of the first observatories in the world to involve several passive and active ground-based instruments installed in multiple locations, managed by different research institutions, in a highly polluted megacity affected by coastal weather regimes. BAQUNIN has been promoted by the European Space Agency to establish an experimental research infrastructure for the validation of present and future satellite atmospheric products and the in-depth investigation of the planetary and urban boundary layers. Here, the main characteristics of the three sites are described, providing information about the complex instrumental suite and the produced data. The supersite adopts a policy of free sharing of its validated dataset with the community. Finally, the BAQUNIN potential is demonstrated with a case study involving a major fire that occurred in a waste treatment plant near the urban center of Rome, and the consequent investigation of the plume properties revealed by different instruments.