Articles | Volume 17, issue 24
Atmos. Chem. Phys., 17, 15271–15292, 2017
Atmos. Chem. Phys., 17, 15271–15292, 2017

Research article 22 Dec 2017

Research article | 22 Dec 2017

Source attribution using FLEXPART and carbon monoxide emission inventories: SOFT-IO version 1.0

Bastien Sauvage1, Alain Fontaine1, Sabine Eckhardt3, Antoine Auby4, Damien Boulanger2, Hervé Petetin1, Ronan Paugam5, Gilles Athier1, Jean-Marc Cousin1, Sabine Darras3, Philippe Nédélec1, Andreas Stohl3, Solène Turquety6, Jean-Pierre Cammas7, and Valérie Thouret1 Bastien Sauvage et al.
  • 1Laboratoire d'Aérologie, Université de Toulouse, CNRS, UPS, France
  • 2Observatoire Midi-Pyrénées, Toulouse, France
  • 3NILU, Norwegian Institute for Air Research, Kjeller, Norway
  • 4CAP HPI, Leeds, United Kingdom
  • 5King's College, Dept. Geog, London, United Kingdom
  • 6Laboratoire de Météorologie Dynamique/IPSL, UPMC Univ. Paris 6, Paris, France
  • 7Observatoire des Sciences de l'Univers de la Réunion (UMS 3365) et Laboratoire de l'Atmosphère et des Cyclones (UMR 8105), Université de la Réunion, Saint-Denis, La Réunion, France

Abstract. Since 1994, the In-service Aircraft for a Global Observing System (IAGOS) program has produced in situ measurements of the atmospheric composition during more than 51 000 commercial flights. In order to help analyze these observations and understand the processes driving the observed concentration distribution and variability, we developed the SOFT-IO tool to quantify source–receptor links for all measured data. Based on the FLEXPART particle dispersion model (Stohl et al., 2005), SOFT-IO simulates the contributions of anthropogenic and biomass burning emissions from the ECCAD emission inventory database for all locations and times corresponding to the measured carbon monoxide mixing ratios along each IAGOS flight. Contributions are simulated from emissions occurring during the last 20 days before an observation, separating individual contributions from the different source regions. The main goal is to supply added-value products to the IAGOS database by evincing the geographical origin and emission sources driving the CO enhancements observed in the troposphere and lower stratosphere. This requires a good match between observed and modeled CO enhancements. Indeed, SOFT-IO detects more than 95 % of the observed CO anomalies over most of the regions sampled by IAGOS in the troposphere. In the majority of cases, SOFT-IO simulates CO pollution plumes with biases lower than 10–15 ppbv. Differences between the model and observations are larger for very low or very high observed CO values. The added-value products will help in the understanding of the trace-gas distribution and seasonal variability. They are available in the IAGOS database via The SOFT-IO tool could also be applied to similar data sets of CO observations (e.g., ground-based measurements, satellite observations). SOFT-IO could also be used for statistical validation as well as for intercomparisons of emission inventories using large amounts of data.

Short summary
We provide the scientific community with a SOFT-IO tool based on the coupling of Lagrangian modeling with emission inventories and aircraft CO measurements, which is able to calculate the contribution of the sources and geographical origins of CO measurements, with good performances. Calculated CO added-value products will help scientists in interpreting large IAGOS CO data set. SOFT-IO could further be applied to other CO data sets or used to help validate emission inventories.
Final-revised paper