Skip navigation.



Aerosol particles in the atmosphere have an important influence on the radiative balance through directly reflecting sun light back into space (and sometimes absorbing part of it and converting it into heat) as well as through acting as cloud condensation nuclei to alter cloud properties and their radiative effects. Aerosol particles do also impact human health (as particulate matter near the surface), renewable energies (by reducing solar irradiance available for power plants) and traffic (desert dust storms, volcanic eruptions).


The ultimate objective of Aerosol_cci is to provide independently validated high quality algorithms for the processing of long-term records of global aerosol properties from European satellite instruments.

The current project Aerosol_cci+ (03/2019 - 02/2022) focuses on further algorithm improvements for the dual view sensor line and in parituclar the Sentinel-3 SLSTR instrument together with two user case studies (data assimialtion for climate services and sicnece 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 (10/2016 - 09/2018) and C3S_312b_Lot2 (10/2018 - 06/2021).

In response to the requirements of the Global Climate Observing System (GCOS) and the AEROCOM international modelling community the Aerosol_cci (1 and 2) project has focused between 2010 and 2019 on :

  • improving and assessing algorithms for total aerosol optical depth
  • improvingand assessing algorithms for fine / coarse mode aerosol optical depth and for dust optical depth
  • improving and assessing algorithms for stratospheric extinction profiles
  • testing algorithms for further aerosol quantitites (effective layer eight, single scattering albedo / absorbing aerosol optical depth)
  • work with the AEROCOM community as primary user and conduct dedivcated user case studies to the applicability of those datasets, their strengths and weaknesses

Latest news 

New contract Aerosol_cci+ kicked off [11/03/2019]

The new Aerosol_cci+ contract with focus on SLSTR algorithm development and evaluation, two user case studies and community support held its kickoff meeting in Harwell at ESA ECSAT on 11 March 2019. In its first period the new project will update its user requireemnts and valdiation plan and work on to improve retrieval algorithms from findings of the predecessor project Aerosol_cci2.

Final Aerosol_cci2 datasets available and validated [15/12/2017]

Final versions of ESA Aerosol_cci products are freely available at and
(unrestricted online access: account: cci; password: cci)

The products provided on this server are openly and freely available. No warranty is given by their providers. Users are obliged to acknowledge the ESA Climate Change Initiative and in particular its Aerosol_cci project together with the individual service provider.
We encourage interaction with the service providers on proper use of the products and would like to receive a copy of all reports and publications using the datasets. An offer of co-authorship should be considered, if the CCI datasets constitute a major component of a scientific publication.


About the project

Aerosol_cci (Phase 1) was run from 7/2010 until 2/2014 followed by Phase 2 (Aerosol_cci2) from 5/2014 - 10/2019 (including a small bridging option(10/2018 - 10/2019). A new project under the CCI extension Aerosol_cci+ for new research on aerosol ECVs has started in 03/2019 and will run for 36 months.

The project team

The Aerosol_cci+ project team is composed of following partners.

Project coordination

German Aerospace Center (DLR)
Dr. Thomas Popp is science leader and project manager.
EO expert team (retrieval development and validation)
Swansea University (SU)
Dr. Peter North and his team are focusing on further improving the SLSTR (and ATSR) retrieval algorithms used in Aerosol_cci2.


Dr. Yves Govaerts and his team are working on a new SLSTR retrieval based on SEVIRI heritage.
German Aerospace Center (DLR)
Dr. Thomas Popp and his team are working on the validation of aeroosl datasets with AERONET and coordinate the AEROSAT network.
Finnish Meteorological Institute (FMI)
Drs. Larisa Sogacheva and Pekka Kolmonen and Prof. Gerrit de Leeuw are working on intercomparisons of aerosol datasets with other satellite-based datasets and support AEROSAT experiments.
Climate modelling team
Max-Planck Institute for Meteorology (MPI)
Dr. Stefan Kinne is working on a scientific user case study on using SLSTR (and other) information to constrain radiative forcing and provides links to the AEROCOM modelling community.
European Centre for Medium Range Weather Forecasts (ECMWF)
Drs. Angela Benedetti and Rossana Dragani are working on a user case study for data assimilation of SLSTR areosol data and linking to the data assimialtion / forecasting / climate service communitíes.
The Aerosol_cci+ project is rooted deeply into the developments of its predecessor project.s Aerosol_cci phase1 and phase 2 project teams were composed of following partners.

German Aerospace Center (DLR): Drs. Thomas Popp (co science leader, project manager), Miriam Kosmale (dpt. project manager), Lars Klüser (EO experts), Julian Meyer-Arnek (system engineer).

Finnish Meteorological Institute (FMI): Prof. Dr. Gerrit de Leeuw (co science leader), Drs. Larisa Sogacheva, Pekka Kolmonen (EO experts).
Oxford University (UO): Drs. Don Grainger, Adam Povey (EO experts).
Rutherford Appleton Laboratory (RAL): Drs. Caroline Poulson, Gareth Thomas, (EO experts), Richard Siddans (system engineer)
Swansea University (SU): Drs. Peter North, Andreas Heckel (EO experts)
University of Bremen (UB): Drs. Marco Vountas, Linlu Mei (EO experts)
Lille University - Laboratoire d'Optique Atmosphérique (LOA): Prof. Dr. Oleg Dubovik, Drs. Pavel Litvinov (EO experts), Jacques Descloitres (system engineer)
Royal Netherlands Meteorological Institute (KNMI): Drs. Pepijn Veefkind, Gijsbert Tilstra (EO experts, user).
Belgian Institute for Space Aeronomie (BIRA): Drs. Christine Bingen, Sophie Vandebussche (EO experts)
rayference: Dr. Yves Govaerts (EO expert)
Universite Libre de Brussels: Prof. Lieven Clarisse (EO expert)
Ecole Polytechnique (LMD): Dr. Virginie Capelle (EO expert)
Norwegian Meteorological Institute (MetNo): Drs. Michael Schulz, Jan Griesfeller (user, valdiation expert)
Max-Planck Institute for Meteorology (MPI): Drs. Stefan Kinne, Christoph Brühl (user, valdiation expert)
Norwegian Institute for Air Reearch (NILU): Dr. Kerstin Stebel (validation expert)
Eidgenössische Technische Hochschule Zürich (ETHZ): Prof. Dr. Ulrike Lohmann, Dr. David Neubaur (user)
Barcelona Supercomputing Center (BSC): Drs. Enza di Tomaso, Sara Basart (user)
London Metropolitan university: Dr. Yong Xue (validation expert)
Freie Universität Berlin (FUB): Prof. Dr. Jürgen Fischer, Dr. Rene Preusker (EO expert)
HYGEOS: Dr. Didier Ramon (EO expert)
Paul Scherrer Institut (PSI): Dr. Paul Zieger (validation expert)

Resources, data and documents


Product overview
The latest global products including  uncertainties are provided via the CCI Open Data Portal:

Name / version Parameter coverage Provider
AATSR_ADV and ATSR2_ADV/ 2.31 AOD, FMAOD 1995-2012 (FMI)
AATSR_ORAC and ATSR2_ORAC / 4.01 AOD, FMAOD 1995-2012 (Oxford University / RAL)
AATSR_SU and ATSR_SU / 4.3 AOD, FMAOD 1995-2012 (Swansea University)

In addition an ensemble dataset (v2.6) from the 3 ATSR datasets (using weighting with uncertainties contained in the products where at least two of the three retrievals have valid results) is provided.

IASI_ULB / 8 Dust AOD 2007-2015 (ULB)
IASI_LMD / 2.1 Dust AOD 2007-2015 (LMD)
IASI_IMARS / 5.2 Dust AOD 2007-2015 (DLR)
IASI_MAPIR / 3.51 Dust AOD 2007-2015 (BIRA)

PARASOL/GRASP 0.08 AOD, FMAOD, SSA 2005-2013 4selected regions (LOA)

GOMOS_AERGOM / 3.00 extinction 2002-2012 (BIRA)

Further data from the first phase are also available:
MERIS_ALAMO / 2.2 AOD 1-12 2008 Ocean only (ICARE)

Available on request (as co-funded by Aerosol_cci) is
Multi-sensor_AAI/1.7 AAI 1978-2012 (KNMI)

Additionally, an experimental geostationary dataset (2008) is provided with the CISAR algorithm (v10., rayference).

The four AATSR datasets are similar on their quality over land to MODIS / MISR (but with weaker coverage and less accuracy for high AOD values). The four ATSR-2 datasets cover a historic period observed only by few other satellite aeroosl datasets.

The four IASI datasets contain a complementary aerosol property (mineral dust AOD).

PARASOL / GRASP provides several consistent aerosol properties within one retrieval.

GOMOS / AERGOM provides stratospheric extinction profile datasets.

The multi-sensor AAI record provides qualitative information on aerosol absorption.

The MERIS dataset provides wider swath width than AATSR (both onboard ENVISAT).

The CISAR algorithm provides hourly AOD.


From the new Aerosol_cci+ project the first set of definition documents is available:

User Requirements Document (URD), Version 4.3, 08.10.2019

Product Validation Plan (PVP), Version 1.2, 08.10.2019

The final report for the Aerosol_cci project is available with validation of the new released datasets is summarized in the Product Validation and Inter-comparison Report (PVIR), Version 3.41, 21.12.2017. Example applications of the products are discussed in the Climate Assessment Report (CAR), Version 2.7, 08.01.2018.
A summary of the strengths and weaknesses of the products is provided in the Product User Guide (PUG), Version 2.3, 08.01.2018.

All key documents are listed below:

Contact us / support

Use the following emails to contact the Aerosol_cci+ team:

  • Scientific leader: thomas.popp[at]
  • ESA technical officer: simon.pinnock[at]