Journal cover Journal topic
Atmospheric Measurement Techniques An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

Journal metrics

  • IF value: 3.248 IF 3.248
  • IF 5-year value: 3.650 IF 5-year 3.650
  • CiteScore value: 3.37 CiteScore 3.37
  • SNIP value: 1.253 SNIP 1.253
  • SJR value: 1.869 SJR 1.869
  • IPP value: 3.29 IPP 3.29
  • h5-index value: 47 h5-index 47
  • Scimago H index value: 60 Scimago H index 60
Volume 10, issue 10 | Copyright
Atmos. Meas. Tech., 10, 3697-3718, 2017
https://doi.org/10.5194/amt-10-3697-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.

Research article 09 Oct 2017

Research article | 09 Oct 2017

Comparison of the GOSAT TANSO-FTS TIR CH volume mixing ratio vertical profiles with those measured by ACE-FTS, ESA MIPAS, IMK-IAA MIPAS, and 16 NDACC stations

Kevin S. Olsen1, Kimberly Strong1, Kaley A. Walker1,2, Chris D. Boone2, Piera Raspollini3, Johannes Plieninger4, Whitney Bader1,5, Stephanie Conway1, Michel Grutter6, James W. Hannigan7, Frank Hase4, Nicholas Jones8, Martine de Mazière9, Justus Notholt10, Matthias Schneider4, Dan Smale11, Ralf Sussmann4, and Naoko Saitoh12 Kevin S. Olsen et al.
  • 1Department of Physics, University of Toronto, Toronto, Ontario, Canada
  • 2Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada
  • 3Istituto di Fisica Applicata “N. Carrara” (IFAC) del Consiglio Nazionale delle Ricerche (CNR), Florence, Italy
  • 4Institut für Meteorologie und Klimaforschung, Karlsruhe Institute of Technology, Karlsruhe, Germany
  • 5Institute of Astrophysics and Geophysics, University of Liège, Liège, Belgium
  • 6Centro de Ciencias de la Atmósfera, Universidad Nacional Autónoma de México, Mexico City, Mexico
  • 7Atmospheric Chemistry Division, National Center for Atmospheric Research, Boulder, CO, USA
  • 8Centre for Atmospheric Chemistry, University of Wollongong, Wollongong, Australia
  • 9Belgisch Instituut voor Ruimte-Aëronomie-Institut d'Aéronomie Spatiale de Belgique (IASB-BIRA), Brussels, Belgium
  • 10Institute for Environmental Physics, University of Bremen, Bremen, Germany
  • 11National Institute of Water and Atmospheric Research Ltd (NIWA), Lauder, New Zealand
  • 12Center for Environmental Remote Sensing, Chiba University, Chiba, Japan

Abstract. The primary instrument on the Greenhouse gases Observing SATellite (GOSAT) is the Thermal And Near infrared Sensor for carbon Observations (TANSO) Fourier transform spectrometer (FTS). TANSO-FTS uses three short-wave infrared (SWIR) bands to retrieve total columns of CO2 and CH4 along its optical line of sight and one thermal infrared (TIR) channel to retrieve vertical profiles of CO2 and CH4 volume mixing ratios (VMRs) in the troposphere. We examine version 1 of the TANSO-FTS TIR CH4 product by comparing co-located CH4 VMR vertical profiles from two other remote-sensing FTS systems: the Canadian Space Agency's Atmospheric Chemistry Experiment FTS (ACE-FTS) on SCISAT (version 3.5) and the European Space Agency's Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) on Envisat (ESA ML2PP version 6 and IMK-IAA reduced-resolution version V5R_CH4_224/225), as well as 16 ground stations with the Network for the Detection of Atmospheric Composition Change (NDACC). This work follows an initial inter-comparison study over the Arctic, which incorporated a ground-based FTS at the Polar Environment Atmospheric Research Laboratory (PEARL) at Eureka, Canada, and focuses on tropospheric and lower-stratospheric measurements made at middle and tropical latitudes between 2009 and 2013 (mid-2012 for MIPAS). For comparison, vertical profiles from all instruments are interpolated onto a common pressure grid, and smoothing is applied to ACE-FTS, MIPAS, and NDACC vertical profiles. Smoothing is needed to account for differences between the vertical resolution of each instrument and differences in the dependence on a priori profiles. The smoothing operators use the TANSO-FTS a priori and averaging kernels in all cases. We present zonally averaged mean CH4 differences between each instrument and TANSO-FTS with and without smoothing, and we examine their information content, their sensitive altitude range, their correlation, their a priori dependence, and the variability within each data set. Partial columns are calculated from the VMR vertical profiles, and their correlations are examined. We find that the TANSO-FTS vertical profiles agree with the ACE-FTS and both MIPAS retrievals' vertical profiles within 4% (± ∼  40ppbv) below 15km when smoothing is applied to the profiles from instruments with finer vertical resolution but that the relative differences can increase to on the order of 25% when no smoothing is applied. Computed partial columns are tightly correlated for each pair of data sets. We investigate whether the difference between TANSO-FTS and other CH4 VMR data products varies with latitude. Our study reveals a small dependence of around 0.1% per 10 degrees latitude, with smaller differences over the tropics and greater differences towards the poles.

Publications Copernicus
Download
Short summary
The primary instrument on the Greenhouse gases Observing SATellite (GOSAT) is the Thermal And Near infrared Sensor for carbon Observations (TANSO) Fourier transform spectrometer (FTS). TANSO-FTS has a thermal infrared channel to retrieve vertical profiles of CO2 and CH4 volume mixing ratios in the troposphere. We compare the retrieved vertical profiles of CH4 from TANSO-FTS with those from two other spaceborne FTSs and with ground-based FTS observatories to assess their quality.
The primary instrument on the Greenhouse gases Observing SATellite (GOSAT) is the Thermal And...
Citation
Share