1- 1Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Physik der Atmosphäre, Weßling, Germany (dietrich.feist@dlr.de)
- *A full list of authors appears at the end of the abstract
Satellite remote sensing of global greenhouse gas (GHG) concentrations provides invaluable information about GHG sources and sinks, supporting efficient climate mitigation policies. Recently, the accuracy targets of upcoming GHG satellite missions have become increasingly stringent (±2 ppb for CH4; ±1 ppm for CO2).
Up to now, calibration and traceability of satellite GHG observations relies on two networks of ground-based remote sensing stations: the Total Carbon Column Observing Network (TCCON) and the COllaborative Carbon Column Observing Network (COCCON). Both networks are able to observe the same quantity as the satellite instruments: column-averaged dry-air mole fraction of CO2 and CH4. They also observe N2O, which will likely become another key GHG to be monitored in the future. For traceability, both networks rely on regular aircraft and balloon measurements with in-situ instruments that are traceable to the WMO scale for GHGs.
In 2025, the new project 24GRD06 MetCTG was started to improve the traceability of remote-sensing observations of atmospheric greenhouse gases, both from the ground as well as from satellites. This will be achieved by greatly improving the accuracy of the underlying spectral line parameters through theoretical work as well as in the lab. Methods will be established to make these improved parameters SI-traceable from end to end. The results will be validated in the field with in situ and ground-based observations. This will establish an alternative traceability chain to SI for ground-based and satellite retrievals. In the long term, the work should improve the consistency among ground-based sites and reduce the need for costly aircraft calibrations. Satellite GHG missions, which rely on these ground-based observations for calibration and validation, will benefit from an improved data comparability across missions and products.
More information about the 24GRD06 MetCTG project is available at https://www.metctg.ptb.de/.
Acknowledgments: The project 24GRD06 MetCTG receives funding from the European Partnership on Metrology, co-financed from the European Union’s Horizon Europe Research and Innovation Programme and by the Participating States.
Manfred Birk (1), Domenico Prudenzano (1), Christian Röske (1), Georg Wagner (1), Kirill Berezkin (2), Gang Li (2), Alexandra Lüttschwager (2), Christian Monte (2), Rainer Stosch (2), Dieter Taubert (2), Andre Butz (3), Frank Hase (4), Jia Chen (5), Rigel Kivi (6), Jeremias Seppa (7), Raymond Armante (8), Ha Tran (8), Alain Campargue (9), Samir Kassi (9), Didier Mondelain (9), Giulio Beltramino (10), Francesca Durbiano (10), Diana Enescu (10), Vito Fernicola (10), Lucia Rosso (10), Francesca Rolle (10), Michela Sega (10), Hanjun Eun (11), Kiryong Hong (11), Sangil Lee (11), Maciej Chomski (12), Maciej Gruszczynski (12), Przemyslaw Glowacki (12), Daniel Lisak (13), Piotr Masłowski (13), Roman Ciuryło (13), Simone Brunamonti (14), Joachim Mohn (14), Patrick Siegwolf (14), Bela Tuzson (14), Andrew Whitehill (14), Paul Brewer (15), Marc Coleman (15), Tom Gardiner (15), Christoph Nehrbass-Ahles (15), Ruth Pearce (15), Chris Rennick (15), Jonathan Tennyson (16), Oleg Polyansky (16), Jeremy Harrison (17), Can Gozonunde (18), and Humbet Nasibli (18). Affiliations: (1) Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Physik der Atmosphäre, Weßling, Germany; (2) Physikalisch-Technische Bundesanstalt, Braunschweig, Germany; (3) Heidelberg University, Heidelberg, Germany; (4) Institut für Meteorologie und Klimaforschung (IMK-ASF), Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany (5) Technical University of Munich, Munich, Germany; (6) Finnish Meteorological Institute, Sodankylä, Finland; (7) VTT Technical Research Centre of Finland, Espoo, Finland; (8) Laboratoire de météorologie dynamique, Institute Pierre-Simon Laplace, Paris, France; (9) CNRS, LIPhy, Université Grenoble Alpes, Grenoble, France; (10) INRIM, National Metrology Institute of Italy, Torino, Italy; (11) Korea Research Institute of Standards and Science, Daejeon, South Korea; (12) Central Office of Measures, Warsaw, Poland; (13) Nicolaus Copernicus University, Torun, Poland; (14) Empa, Dübendorf, Switzerland; (15) National Physical Laboratory, Teddington, United Kingdom; (16) University College London, London, United Kingdom; (17) University of Leicester, Leicester, United Kingdom; (18) Scientific and Technological Research Council of Türkiye (TÜBİTAK), Gebze, Turkey.
How to cite: Feist, D. G. and the MetCTG Team: A new way to implement SI-traceability in greenhouse gas remote-sensing observations: the Metrology for Comparable and Trustworthy Greenhouse gas remote sensing datasets (24GRD06 MetCTG) project, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-14207, https://doi.org/10.5194/egusphere-egu26-14207, 2026.
