Metrology for aerosol optical properties

Short Name: MAPP, Project Number: 19ENV04
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Empty road leads into sunrise

Improving methods and instrumentation to better understand the contribution of atmospheric aerosols to climate change

Atmospheric aerosols absorb or scatter solar radiation contributing the largest uncertainty to estimates and interpretations of climate change.   Data for aerosol effects on sky radiation is typically collected by optical radiometers which are largely lacking traceability to the SI. Furthermore, radiometer calibration, using artefacts, is performed outdoors at only two locations world-wide. Requiring perfect weather, the resulting long calibration times lead to excessive downtimes at monitoring stations. SI traceable devices capable of on-site calibration would significantly speed up the calibration process, allowing more data to be obtained.


Building upon the work of the EMRP projects SolarUV, METEOC-2 and ATMOZ the project has developed methods and SI-traceable devices for both laboratory and in-field calibrations of radiometers measuring solar and lunar irradiance. Data on the measurement uncertainty for a range of aerosol optical properties, retrieved from remote sensing-based instruments were also  developed along with validated methods linking ground-based measurements to satellite-based data.


At the end of the project in 2023 results obtained will help shorten the radiometer calibration chain, reduce the downtime of monitoring networks and generate traceable data to support societies in adapting to a changing climate.


Project website
Other Participants
Agencia Estatal de Meteorología (Spain)
Centre National de la Recherche Scientifique (France)
Consiglio Nazionale delle Ricerche (Italy)
The University of Reading (United Kingdom)
Universidad De Valladolid (Spain)
Universitat de València (Spain)
Université de Lille (France)