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01 July 2011

The MERIS 3rd Reprocessing has now been completed and the data are available online via ftp at the UK-PAC.

The ftp site currently includes the full 2008-2009-2010 Level 1 and Level 2 reprocessed dataset. The entire reprocessed dataset from, 29 April 2002 to date, will gradually be made available online over the coming weeks. The data is structured on the ftp server by product-type/year/month/day and the files are compressed.

In a second step, the full data set will also be provided via a new MERCI server (opening planned in autumn 2011).

The Reprocessing has been carried out using the MERIS Ground Segment (MEGS) Processor Version 8.0, which is fully equivalent to the new operational processor IPF V6.03 that will be used for the real time production at the stations in the near future.

The main 3rd reprocessing improvements include:

Level 1:

  • Updated radiometric model and coefficients

Level 2:

  • Revised pixel classification and flagging
  • Vicarious adjustment of Marine Reflectances
  • New Bright Pixel Atmospheric Correction (BPAC) algorithm
  • Updated Radiative Transfer LUTs and interpolation methodologies
  • New Case_2 waters atmospheric correction for Algal_2, TSM and Yellow substance products
  • New Water Vapour retrieval over land algorithm
  • New Surface Pressure algorithm over Land

Documentation:

More detailed information on all of the changes implemented for the 3rd Reprocessing are available online:

All updated documentation related to the 3rd Reprocessing will be placed on the MERIS Product Handbook website (http://envisat.esa.int/handbooks/) in the near future.

3rd Reprocessing products can be identified via:

  • The value of the Processing Stage value flag in the filename (see Section 2.2.1.2 of the MERIS Product Handbook for details) and Main Product Header (MPH) being set to "R" (MER_RR__1PR, MER_RR__2PR)
  • The PROC_VERSION field of the MPH being set to "MEGS/8.0"

PLEASE NOTE: Products currently available from the ESA MERIS Rolling Archives (NRT) and the MERCI MERIS Catalogue (Consolidated) will continue to be processed using the previous version of the processor (IPF 5.06 - equivalent to MEGS 7.4).

For the next months, the only access to the 3rd MERIS RR reprocessing version is done via the new ftp access at the UK-PAC.

The operational IPF processor will be updated to be consistent with MEGS 8.0 in the near future, and a separate user notification will be published with further details of the switch at the acquisition stations.

The Agency is planning to release access to the MERIS 3rd Reprocessing products from a new MERCI server in autumn 2011. With the release of this new MERCI download service, the current access to the MERCI MERIS Catalogue (Consolidated) will be dismissed.

Access to the MERIS RR 3rd Reprocessing via ftp can be provided to existing ESA proposals and/or Registrations by contacting EO Helpdesk or through a new Registration on the ESA EOPI Portal.

Please contact EO Help for further clarification required.