Journal cover Journal topic
Atmospheric Chemistry and Physics An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

Journal metrics

  • IF value: 5.414 IF 5.414
  • IF 5-year value: 5.958 IF 5-year
    5.958
  • CiteScore value: 9.7 CiteScore
    9.7
  • SNIP value: 1.517 SNIP 1.517
  • IPP value: 5.61 IPP 5.61
  • SJR value: 2.601 SJR 2.601
  • Scimago H <br class='hide-on-tablet hide-on-mobile'>index value: 191 Scimago H
    index 191
  • h5-index value: 89 h5-index 89
Preprints
https://doi.org/10.5194/acp-2020-603
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-2020-603
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

  09 Jul 2020

09 Jul 2020

Review status
This preprint is currently under review for the journal ACP.

Inverse modelling of carbonyl sulfide: implementation, evaluation and implications for the global budget

Jin Ma1, Linda M. J. Kooijmans2, Ara Cho2, Stephen A. Montzka3, Norbert Glatthor4, John R. Worden5, Le Kuai5, Elliot L. Atlas6, and Maarten C. Krol1,2 Jin Ma et al.
  • 1Institute for Marine and Atmospheric Research, Utrecht University, Utrecht, the Netherlands
  • 2Meteorology and Air Quality, Wageningen University & Research, Wageningen, the Netherlands
  • 3National Oceanic and Atmospheric Administration (NOAA), Boulder, CO, USA
  • 4Institute of Meteorology and Climate Research, Karlsruhe Institute of Technology, Karlsruhe, Germany
  • 5Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
  • 6Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, USA

Abstract. Carbonyl sulfide (COS) has the potential to be used as a climate diagnostic due to its close coupling to the biospheric uptake of CO2 and its role in the formation of stratospheric aerosol. The current understanding of the COS budget, however, lacks COS sources, which have previously been allocated to the tropical ocean. This paper presents a first attempt of global inverse modelling of COS within the 4-Dimensional variational data-assimilation system of the TM5 chemistry transport model (TM5-4DVAR) and a comparison of the results with independent COS observations. We focus on the global COS budget, including COS production from its precursors carbon disulfide (CS2) and dimethyl sulfide (DMS). To this end, we implemented COS uptake by soil and vegetation from an updated biosphere model (SiB4), and new inventories for anthropogenic and biomass burning emissions. The model framework is capable of closing the COS budget by optimizing for missing emissions using NOAA observations in the period 2000–2012. The addition of 432 Gg S a−1 COS is required to obtain a good fit with NOAA observations. This missing source shows little year-to-year variations, but considerable seasonal variations. We found that the missing sources are likely located in the tropical regions, and an overestimated biospheric sink in the tropics cannot be ruled out. Moreover, high latitudes in the Northern Hemisphere require extra COS uptake or reduced emissions. HIPPO aircraft observations, NOAA airborne profiles from an ongoing monitoring program, and several satellite data sources are used to evaluate the optimized model results. This evaluation indicates that COS in the free troposphere remains underestimated after optimization. Assimilation of HIPPO observations slightly improves this model bias, which implies that additional observations are urgently required to constrain sources and sinks of COS. We finally find that the biosphere flux dependency on surface COS mixing ratio may substantially lower the fluxes of the SiB4 biosphere model over strong uptake regions. In planned further studies we will implement this biosphere dependency, and additionally assimilate satellite data with the aim to better separate the role of the oceans and the biosphere in the global COS budget.

Jin Ma et al.

Interactive discussion

Status: open (until 03 Sep 2020)
Status: open (until 03 Sep 2020)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
[Subscribe to comment alert] Printer-friendly Version - Printer-friendly version Supplement - Supplement

Jin Ma et al.

Viewed

Total article views: 137 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
80 52 5 137 14 7 6
  • HTML: 80
  • PDF: 52
  • XML: 5
  • Total: 137
  • Supplement: 14
  • BibTeX: 7
  • EndNote: 6
Views and downloads (calculated since 09 Jul 2020)
Cumulative views and downloads (calculated since 09 Jul 2020)

Viewed (geographical distribution)

Total article views: 207 (including HTML, PDF, and XML) Thereof 207 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 

Cited

Saved

No saved metrics found.

Discussed

No discussed metrics found.
Latest update: 11 Aug 2020
Publications Copernicus
Download
Short summary
Carbonyl sulfide is an important trace gas in the atmosphere and useful to estimate gross primary productivity in ecosystem, but its sources and sinks remain highly uncertain. Therefore, we applied inverse model system TM5-4DVAR to better constrain the global budget. Our finding is in line with earlier studies, pointing to missing sources in tropics and more uptake in high latitudes. We also stress on the necessity of more ground-based observations and satellite data assimilation in future.
Carbonyl sulfide is an important trace gas in the atmosphere and useful to estimate gross...
Citation