The data from the 4th MERIS reprocessing has been released to users and is now freely available from the new ESA Online Dissemination Service for MERIS.

The complete Envisat MERIS Full Resolution (FR) and Reduced Resolution (RR) archives spanning from May 2002 to April 2012 have been fully reprocessed with the same processor configuration (MEGS 9).

The main changes with respect to the former (3rd) product baseline for MERIS are the following:

• Alignment of the MERIS and Sentinel-3/OLCI data processing chains to ensure a continuity of the products derived from these two instruments
• The former MERIS Envisat data format (.N1) has been changed in favour of the Sentinel-3 SAFE format based on a folder of NetCDF files including an xml manifest file
• A number of algorithm and auxiliary data evolutions have been implemented according to recommendations by the MERIS Quality Working Group (QWG)
• The source of the meteo data included in the Level 1 and Level 2 products is now ECMWF Era-Interim

For further information on the MERIS 4th reprocessing data, please refer to the Readme File, the MERIS Validation and Algorithm 4th Reprocessing Report and the MERIS Data Description pages.

The new MERIS dissemination service is collection based and can be freely searched by users.

Download of selected data products requires login with a personal ESA EO Sign In account. If you do not already have an EO Sign In account, please self-register one to download data.

Please note that the two MERCI (MERIS Catalogue and Inventory) instances hosting the MERIS FR and MERIS RR 3rd reprocessing data are being replaced by the new dissemination service for MERIS.

Dismissal of MERCI is planned to take place on 15 September 2020.

Should you need any additional clarification or support please contact the ESA EO Help Desk.