Journal cover Journal topic
Biogeosciences An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

IF value: 3.480
IF 5-year value: 4.194
IF 5-year
CiteScore value: 6.7
SNIP value: 1.143
IPP value: 3.65
SJR value: 1.761
Scimago H <br class='widget-line-break'>index value: 118
Scimago H
h5-index value: 60
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

  05 Nov 2020

05 Nov 2020

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

Carbonyl Sulfide: Comparing a Mechanistic Representation of the Vegetation Uptake in a Land Surface Model and the Leaf Relative Uptake Approach

Fabienne Maignan1, Camille Abadie1, Marine Remaud1, Linda M. J. Kooiijmans2, Kukka-Maaria Kohonen3, Róisín Commane4, Richard Wehr5, J. Elliott Campbell6, Sauveur Belviso1, Stephen A. Montzka7, Nina Raoult1, Ulli Seibt8, Yoichi P. Shiga9, Nicolas Vuichard1, Mary E. Whelan10, and Philippe Peylin1 Fabienne Maignan et al.
  • 1Laboratoire des Sciences du Climat et de l’Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, Gif-sur-Yvette, France
  • 2Meteorology and Air Quality, Wageningen University and Research, Wageningen, The Netherlands
  • 3Institute for Atmospheric and Earth System Research (INAR)/Physics, Faculty of Science, University of Helsinki, Helsinki, Finland
  • 4Dept. Earth & Environmental Sciences, Lamont-Doherty Earth Observatory of Columbia University, New York, NY 10964, USA
  • 5Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, USA
  • 6Sierra Nevada Research Institute, University of California, Merced, California 95343, USA
  • 7NOAA Global Monitoring Laboratory, Boulder, Colorado, USA
  • 8Dept of Atmospheric & Oceanic Sciences, University of California Los Angeles, California 90095, USA
  • 9Universities Space Research Association, Mountain View, CA, USA
  • 10Department of Environmental Sciences, Rutgers University, New Brunswick, NJ 08901, USA

Abstract. Land surface modelers need measurable proxies to constrain the quantity of carbon dioxide (CO2) assimilated by continental plants through photosynthesis, known as Gross Primary Production (GPP). Carbonyl sulfide (COS), which is taken up by leaves through their stomates and then hydrolysed by photosynthetic enzymes, is a candidate GPP proxy. A former study with the ORCHIDEE land surface model used a fixed ratio of COS uptake to CO2 uptake normalized to respective ambient concentrations for each vegetation type (Leaf Relative Uptake, LRU). COS leaf fluxes were then computed from GPP, and the resulting concentrations were transported with an atmospheric model which included all other known COS fluxes as inputs. Modelled COS concentrations could then be compared to COS measurements from the NOAA air sampling tower network. The LRU approach is known to have limited accuracy since the LRU ratio changes with variables such as Photosynthetically Active Radiation (PAR): while CO2 uptake slows under low light, COS uptake is not light limited. However, the LRU approach has been popular for COS-GPP proxy studies because of its ease of application and apparent low contribution to uncertainty for regional scale applications. In this study we refined the COS-GPP relationship and implemented in ORCHIDEE a mechanistic model that describes COS uptake by continental vegetation. We compared the simulated COS fluxes against measured hourly COS fluxes at two sites, and studied the model behaviour and links with environmental drivers. We performed simulations at global scale, and estimated the global COS uptake by vegetation to be −756 Gg S yr−1, in the middle range of former studies (−490 to −1335 Gg S yr−1). Based on the mechanistic approach in ORCHIDEE, we derived new LRU values for the different vegetation types, ranging between 0.92 and 1.72, close to recently published averages for observed values of 1.21 for C4 and 1.68 for C3 plants. We transported the COS using the monthly vegetation COS fluxes derived from both the mechanistic and the LRU approaches, and evaluated the simulated COS concentrations at NOAA sites. Although the mechanistic approach was more appropriate when comparing to high-temporal-resolution COS flux measurements, both approaches gave similar results when transporting with monthly COS fluxes and evaluating COS concentrations at stations. In our study, uncertainties between these two approaches are of second importance as compared to the uncertainties in the COS global budget, which are currently a limiting factor to the potential of COS concentrations to constrain GPP simulated by land surface models on the global scale.

Fabienne Maignan et al.

Interactive discussion

Status: open (until 17 Dec 2020)
Status: open (until 17 Dec 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

Fabienne Maignan et al.

Fabienne Maignan et al.


Total article views: 206 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
158 46 2 206 1 5
  • HTML: 158
  • PDF: 46
  • XML: 2
  • Total: 206
  • BibTeX: 1
  • EndNote: 5
Views and downloads (calculated since 05 Nov 2020)
Cumulative views and downloads (calculated since 05 Nov 2020)

Viewed (geographical distribution)

Total article views: 152 (including HTML, PDF, and XML) Thereof 152 with geography defined and 0 with unknown origin.
Country # Views %
  • 1



No saved metrics found.


No discussed metrics found.
Latest update: 25 Nov 2020
Publications Copernicus
Short summary
The assimilation of Carbonyl Sulfide (COS) by continental vegetation has been proposed as a proxy for Gross Primary Production (GPP). Using a land surface and a transport models, we compare a mechanistic representation of the plant COS uptake (Berry et al., 2013), to the classical Leaf Relative Uptake (LRU) approach linking GPP and vegetation COS fluxes. We show that at high temporal resolutions a mechanistic approach is mandatory, but at large scales the LRU approach compares similarly.
The assimilation of Carbonyl Sulfide (COS) by continental vegetation has been proposed as a...