Articles | Volume 9, issue 2
Atmos. Meas. Tech., 9, 765–779, 2016
Atmos. Meas. Tech., 9, 765–779, 2016

Research article 02 Mar 2016

Research article | 02 Mar 2016

Validation of revised methane and nitrous oxide profiles from MIPAS–ENVISAT

Johannes Plieninger1, Alexandra Laeng1, Stefan Lossow1, Thomas von Clarmann1, Gabriele P. Stiller1, Sylvia Kellmann1, Andrea  Linden1, Michael Kiefer1, Kaley A. Walker2, Stefan Noël3, Mark E. Hervig4, Martin McHugh5, Alyn Lambert6, Joachim Urbana,†, James W. Elkins7, and Donal Murtagh8 Johannes Plieninger et al.
  • 1Karlsruhe Institute of Technology, Institute for Meteorology and Climate Research, Karlsruhe, Germany
  • 2Department of Physics, University of Toronto, Toronto, Canada
  • 3Institut für Umweltphysik, University of Bremen, Bremen, Germany
  • 4GATS Inc, Driggs, Idaho, USA
  • 5Science and Technology Corporation, Hampton, VA, USA
  • 6Jet Propulsion Laboratory, California Institute of Technology, Pasadena, USA
  • 7NOAA Earth System Research Laboratory, Global Monitoring Division, Boulder, CO, USA
  • 8Department of Earth and Space Sciences, Chalmers University of Technology, Gothenburg, Sweden
  • aformerly at: Department of Earth and Space Sciences, Chalmers University of Technology, Gothenburg, Sweden
  • deceased

Abstract. Improved versions of CH4 and N2O profiles derived at the Institute of Meteorology and Climate Research and Instituto de Astrofísica de Andalucía (CSIC) from spectra measured by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) have become available. For the MIPAS full-resolution period (2002–2004) these are V5H_CH4_21 and V5H_N2O_21 and for the reduced-resolution period (2005–2012) these are V5R_CH4_224, V5R_CH4_225, V5R_N2O_224 and V5R_N2O_225. Here, we compare CH4 profiles to those measured by the Fourier Transform Spectrometer on board of the Atmospheric Chemistry Experiment (ACE-FTS), the HALogen Occultation Experiment (HALOE) and the Scanning Imaging Absorption Spectrometer for Atmospheric CHartographY (SCIAMACHY), to the Global Cooperative Air Sampling Network (GCASN) surface data. We find the MIPAS CH4 profiles below 25 km to be typically higher of the order of 0.1 ppmv for both measurement periods. N2O profiles are compared to those measured by ACE-FTS, the Microwave Limb Sounder on board of the Aura satellite (Aura-MLS) and the Sub-millimetre Radiometer on board of the Odin satellite (Odin-SMR) as well as to the Halocarbons and other Atmospheric Trace Species Group (HATS) surface data. The mixing ratios of the satellite instruments agree well with each other for the full-resolution period. For the reduced-resolution period, MIPAS produces similar values as Odin-SMR, but higher values than ACE-FTS and HATS. Below 27 km, the MIPAS profiles show higher mixing ratios than Aura-MLS, and lower values between 27 and 41 km. Cross-comparisons between the two MIPAS measurement periods show that they generally agree quite well, but, especially for CH4, the reduced-resolution period seems to produce slightly higher mixing ratios than the full-resolution data.

Short summary
We compare concentration profiles of methane and nitrous oxide measured from MIPAS-ENVISAT and derived with a new retrieval setup to those measured by other satellite instruments and to surface measurements. For methane we use profiles measured by ACE-FTS, HALOE and SCIAMACHY; for nitrous oxide we use profiles measured by ACE-FTS, Aura-MLS and Odin-SMR for the comparisons. We give a quantitative bias estimation and compare the estimated errors provided by the instruments.