This dataset collection contains cloud products produced by the Cloud project within the ESA Climate Change Initiative (CCI).

The ultimate objective of the ESA Cloud Climate Change Initiative (Cloud_cci) project is to provide long-term coherent cloud property datasets exploiting the synergic capabilities of different Earth observation missions allowing for improved accuracies and enhanced temporal and spatial sampling better than those provided by the single sources.

CC4CL (Community Cloud Retrieval for Climate) and FAME-C (Freie Universität Berlin AATSR MERIS Cloud) are optimal estimation based retrieval systems providing GCOS cloud property Essential Climate Variables (ECVs) including uncertainty estimates. These global datasets contain cloud fraction, cloud top level estimates (pressure, height, and temperature), cloud thermodynamic phase, spectral cloud albedo, cloud effective radius, cloud optical thickness as well as cloud liquid and ice water content.

The AATSR-MODIS-AVHRR heritage product family obtained by CC4CL is based on measurements from ATSR-2/ERS-2, AATSR/ENVISAT, MODIS/AQUA, MODIS/TERRA, and AVHRR on-board NOAA-7, 9, 11, 12, 14, 15,16, 17, 18,19, and MetOp-A. The second product family contains cloud properties derived from ENVISAT’s AATSR and MERIS observations using the synergetic retrieval system FAME-C.

In the first phase (2010 – 2013) of the Cloud_cci project prototype retrieval versions have been established leading to preliminary results covering 2007, 2008, and 2009, herein referred to as demonstrator datasets. In Phase 2 (2014 – 2016) both retrieval schemes have been substantially improved enhancing the data quality of the cloud products spanning the time period from Jan 1st 1982 to Dec 31st 2014.

Considerations for climate applications:
Due to the short period (i.e. 3 years) of the current available demonstrator datasets, it is not possible to perform long-term data comparisons or to support long-term climate analysis.

Please be aware of the fact that by the end of 2016 at the latest these prototype datasets will be replaced by the complete multi-decadal Cloud_cci climatology (1982 – 2014) together with updated Product User Guide (PUG) and Product Validation and Intercomparison Report (PVIR) documents.

We would like to stress that one of the main objectives in the second phase of the Cloud_cci project has been the further development and improvement of both retrieval schemes and their processing systems. As a consequence, the quality and accuracy of the final cloud products have been considerably improved compared to the currently available demonstrator datasets.