Data from the Odin Sub-Millimetre Radiometer (SMR) reprocessing has been released to users and is now freely available through the Odin/SMR Project Portal.

Odin is part of the ESA Third Party Missions (TPM) programme since 2007. The Odin-SMR Recalibration and Harmonisation project was funded by ESA to create a fully consistent and homogeneous dataset from the many years of satellite operation (2001-present). The reprocessing campaign is a cooperation between Chalmers University of Technology and Molflow.

The Odin SMR data archive has been reprocessed applying a revised calibration scheme and upgraded algorithms. The new dataset represents the outcome from the first full mission reprocessing campaign of the mission. The Level 1b dataset has been entirely consolidated, while Level 2 products were regenerated from the main mesospheric and stratospheric frequency modes (FM 01, 02, 08, 13, 14, 19, 21, 22, 24). Data can be accessed from the Odin/SMR Project Portal, primarily through the web-API, in JSON format and as monthly Level 2 NetCDF files.

The main changes with respect to the former product baseline are the following:

• unified data processing chain throughout the 19 years of measurements
• revised data formats
• improved selection of background spectra for calibration, time and temperature-dependent frequency correction, and automated removal of baseline
• mesospheric and stratospheric products are treated separately
• optimised retrieval settings and improved spectroscopic parameters
• ECMWF Era-Interim meteo data adopted

The new project brings:

• Improved atmospheric spectra and instrument characterisation
• The recovery of the mesospheric carbon monoxide dataset along with the entire mission. In the previous baseline, a failed phase-locked loop caused the frequency to drift and consequent processing failures. A correction was developed and applied (details in Grieco F. et al. 2020)
• A greatly improved ozone dataset from FM 02 (previously FM 01 was used)
• Better consistency between the two mesospheric water vapour products. The new FM 21 data was used as input in the ESA MesosphEO project
• Extensive validation against correlative satellite instruments

The current data version is Level 1b version 8 and Level 2 version 3.

For further information on the Odin/SMR reprocessed data, please refer to the Odin-SMR Project Portal and the documentation available on the portal.

For additional support please contact the ESA EO Help Desk.