Preprints
https://doi.org/10.5194/amt-2021-53
https://doi.org/10.5194/amt-2021-53

  29 Mar 2021

29 Mar 2021

Review status: a revised version of this preprint is currently under review for the journal AMT.

Improvement of Odin/SMR water vapour and temperature measurements and validation of the obtained data sets

Francesco Grieco1, Kristell Pérot1, Donal Murtagh1, Patrick Eriksson1, Bengt Rydberg2, Michael Kiefer3, Maya Garcia-Comas4, Alyn Lambert5, and Kaley A. Walker6 Francesco Grieco et al.
  • 1Department of Space, Earth and Environment, Chalmers University of Technology, Gothenburg, Sweden
  • 2Molflow, Gråbo, Sweden
  • 3Karlsruhe Institute of Technology, Institute of Meteorology and Climate Research, Karlsruhe, Germany
  • 4Instituto de Astrofísica de Andalucía, CSIC, Granada, Spain
  • 5Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States
  • 6Department of Physics, University of Toronto, Toronto, ON, Canada

Abstract. Its long photochemical lifetime makes H2O a good tracer for mesospheric dynamics. Temperature is also an important tracer of seasonal circulation as well as multi-year trends. In this study we present the reprocessing of 18 years of mesospheric H2O and temperature measurements from the Sub-Millimetre Radiometer (SMR) on board the Odin satellite, resulting in a part of the SMR version 3.0 level 2 data set. The previous version of the dataset showed poor accordance with measurements from other instruments, which suggested that the retrieved concentrations and temperature were subject to instrumental artifacts. Different hypotheses have been explored, and the idea of an underestimation of the single sideband leakage turned out to be the most reasonable one. The value of the lowest transmission achievable has therefore been raised to account for greater sideband leakage, and new retrievals have been performed with the new settings. The retrieved profiles extend between 40–100 km altitude and cover the whole globe to reach 85° latitudes. A validation study has been carried out, revealing an overall better accordance with the compared instruments. In particular, relative differences in H2O concentration are always in the ±20 % range between 40 and 70 km and diverge at higher altitudes, while temperature absolute differences are within ± 5 K between 40–80 km (with the exception of FM13 SMR–MLS difference reaching almost 10 K) and also diverge at higher altitudes.

Francesco Grieco et al.

Status: final response (author comments only)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on amt-2021-53', Anonymous Referee #2, 22 Apr 2021
    • AC1: 'Reply on RC1', Francesco Grieco, 03 Jun 2021
  • RC2: 'Comment on amt-2021-53', Anonymous Referee #1, 27 Apr 2021
    • AC2: 'Reply on RC2', Francesco Grieco, 03 Jun 2021

Francesco Grieco et al.

Francesco Grieco et al.

Viewed

Total article views: 388 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
297 78 13 388 3 2
  • HTML: 297
  • PDF: 78
  • XML: 13
  • Total: 388
  • BibTeX: 3
  • EndNote: 2
Views and downloads (calculated since 29 Mar 2021)
Cumulative views and downloads (calculated since 29 Mar 2021)

Viewed (geographical distribution)

Total article views: 326 (including HTML, PDF, and XML) Thereof 326 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 24 Jul 2021
Download
Short summary
We present improved Odin/SMR mesospheric H2O concentration and temperature data sets, reprocessed assuming a bigger sideband leakage of the instrument. The validation study shows how the improved SMR data sets agree better with other instruments' observations than the old SMR version did. Given their unique time extension and geographical coverage, and being H2O a good tracer of mesospheric circulation, the new data sets are valuable for the study of dynamical processes and multi-year trends.