The Sentinel-5 Precursor VAlidatioN and calibraTion Experiment (SVANTE)
Authors: Van Roozendael Michel , Tack Frederik , Merlaud Alexis , Schuettemeyer Dirk , Hase Frank , Richter Andreas , Meier Andreas , Sha Mahesh Kumar , De Mazière Martine , Apituley Arnoud , Nicolae Doina , Calcan Andreaa , Ruhtz Thomas , Crévoisier Cyril , Roiger Anke , Dehn Angelika , Zehner Claus 
Published: March 2020

&lt;p&gt;Launched on 13 October 2017, Sentinel 5 Precursor (S-5p) is the first mission of the Copernicus Programme dedicated to the monitoring of air quality, climate, ozone and UV radiation. The S-5p characteristics, in particular its fine spatial resolution of 3.5 x 5.5 km&lt;sup&gt;2&lt;/sup&gt;, introduce new opportunities for science and applications requiring to carefully assess the quality and validity of the generated data products by comparison with independent measurements and analyses.&lt;/p&gt;&lt;p&gt;While the routine validation and QA/QC of the S-5p operational products is performed within the ESA Mission Performance Center (MPC) based on a limited number of Fiducial Reference Measurements (FRM), additional validation activities including field campaigns are conducted in research mode as part of the S-5p Validation Team (S5PVT). The validation activities bring together various teams and instruments and provide a more in-depth, complete insight into the S-5p instrument performance and the fitness for purpose of its data products.&lt;/p&gt;&lt;p&gt;Here, we present observational deployments planned to take place in 2020-2021 in the context of the Sentinel 5p VAlidatioN and calibraTion Experiment (SVANTE). A first set of activities concentrates on the main S-5p UV-Vis tropospheric products (NO&lt;sub&gt;2&lt;/sub&gt;, HCHO and SO&lt;sub&gt;2)&lt;/sub&gt;. Airborne measurements, including both in-situ spiral and remote sensing mapping flights, are planned over cities and industrial areas in Romania (Bucharest; Jiu valley), the German Ruhr area (Cologne; Duisburg; Dusseldorf) and Berlin, Belgium (Antwerp and Brussels), The Netherlands (Rotterdam and Cabauw), as well as the southern part of The Persian Gulf. These operations will be supported by ground-based measurements using Pandora, MAX-DOAS, car-DOAS, sun-photometer, ceilometer, lidar, etc. Over Berlin and Bucharest, the aim is to perform recurrent airborne observations with hyperspectral imagers in order to accumulate mapping data during approximately one full year, under variable meteorological and air quality conditions, as well as different satellite overpass configurations.&lt;/p&gt;&lt;p&gt;A second set of activities will focus on the validation of the SWIR data products (CO and CH&lt;sub&gt;4&lt;/sub&gt;). COCCON (COllaborative Carbon Column Observing Network) portable low-resolution EM27/SUN FTIR spectrometers will be deployed for an extended period at different sites in order to obtain a good coverage of geophysical parameters and different ground scenes.&lt;/p&gt;&lt;p&gt;Additionally, synergies will be created with large field campaigns, such as the Asian Summer Monsoon Chemical and Climate Impact Project (ACCLIP) and the 2020 HYTES Joint European Campaign, which will provide airborne measurements of NO&lt;sub&gt;2&lt;/sub&gt;, CO and CH&lt;sub&gt;4&lt;/sub&gt; columns and vertical profiles.&lt;/p&gt;&lt;p&gt;The various airborne and ground-based measurements will produce a comprehensive ensemble of reference datasets. For each product, a core team will coordinate validation tasks, making use of data collected in all relevant instrumental deployments.&lt;/p&gt;