The 4th Reprocessing of the AATSR instrument L1B data stemming from the Envisat satellite have now been released to users following successful quality assessment. 

The new AATSR L1B Brightness Temperature/Radiance dataset [ENV_AT_1_RBT] covers the full mission archive from May 2002 to April 2012 and is freely available via the ESA Online Dissemination Service for AATSR. 

Users are strongly advised to update to the 4th Reprocessing AATSR L1B products. 

The dataset has been fully reprocessed into a new product format which aligns it with the format adopted by the instrument’s successor, Sentinel-3 SLSTR, and includes the following updates from the former L1B dataset [ATS_TOA_1P] generated by the AATSR 3rd Reprocessing in 2013: 

• Improved and extended Level 1B dataset, beginning with recovery of Level 0 data, via the reprocessing of all Level 0 data to Level 1A to retain extra instrument information.
• Level 1B products in a Sentinel-SAFE/NetCDF format: a product folder containing NetCDF files and an XML manifest file, holding extensive metadata. This means new information is now available, such as per-pixel uncertainty estimates, associated meteorological data from ECMWF ERA-Interim, instrument scan and pixel quality information, and channel-specific exception and flag values.
• Improved nadir and oblique view colocation, via the use of an updated auxiliary file supplied by STFC RAL Space.
• Incorporation of an advised adjustment to the 12-µm channel, which showed evidence of a small temperature-dependent discrepancy.
• Geolocation improvement via orthogeolocation to a Digital Elevation Model.
• Improved surface classification via use of the Sentinel-3 Land Water Masks.

For further information on the AATSR 4th Reprocessing dataset, please refer to the User Documentation for (A)ATSR 4th Reprocessing, the Readme File and the AATSR Data Description page.  

To be noted that the MERCI catalogue holding the Envisat and ERS (A)ATSR L1B (TOA) and L2 (NR) data from the 3rd Reprocessing will be dismissed by the end of February 2023.

The dedicated ESA FTP server hosting the full set of the (A)ATSR 3rd Reprocessing data will be maintained until release of the 4th Reprocessing L1B data also for ERS ATSR, currently planned during first half of 2023.  

Envisat AATSR Level 2 product generation is now within the remit of the ESA Climate Change Initiative (CCI) Sea Surface Temperature/SST and Land Surface Temperature/LST project teams. Any Level 2 / Level 3 data generation will be made according to the CCI project timelines 

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