Aerosol particles in the atmosphere have an important influence on the Earth's radiative balance by directly reflecting sunlight back into space, as well as absorbing some sunlight and converting it into heat. Aerosols also have an impact on climate by acting as cloud condensation nuclei, which alters cloud properties and their radiative effects. Aerosol particles at surface level impact human health, and are associated with disruption to transport (desert dust storms and volcanic eruptions) and can reduce the solar irradiance available for solar power plants.


The driving objective of the CCI Aerosol project is to provide independently validated, high quality algorithms for processing long-term records of global aerosol properties from European satellite instruments.

The current Aerosol project, running March 2019 to February 2022, focuses on algorithm improvements for the dual view sensor line, in particular the Sentinel-3 SLSTR instrument together with two user case studies (data assimilation for climate services, and science modelling in radiative forcing) and community support (AEROSAT experiments, GEWEX assessment).

The processing of long-term records (6-monthly extensions and complete reprocessing every 2-3 years) has been transferred to the Copernicus Climate Change Service since 2018 within the contracts C3S_312a_Lot5 (October 2016 – September 2018) and C3S_312b_Lot2 (October 2018 – June 2021).

In response to the requirements of the Global Climate Observing System (GCOS) and the AEROCOM international modelling community, the two former phases of the Aerosol have focused on:

Aerosol Phase 1 ran July 2010 to February 2014; Phase 2 ran May 2014 to October 2019. Aerosol_cci+ Phase 1 extended from March 2019 to July 2022. A new project under the CCI extension for new research on aerosol ECVs is foreseen from December 2022 to run for 24 months.