Accurate measurements of co 2 mole fraction in the atmospheric surface layer by an affordable instrumentation

• Main Authors: Keronen, Petri, Reissell, Anni, Chevallier, Frederic, Siivola, Errki, Pohja, Toivi, Hiltunen, Veijo, Hatakka, Juha, Aalto, Tuula, Rivier, Leonard, Ciais, Philippe, Jordan, Armin, Hari, Pertti, Viisanen, Yrjö, Vesala, Timo
• Other Authors: Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Modélisation INVerse pour les mesures atmosphériques et SATellitaires (SATINV), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), ICOS-ATC (ICOS-ATC)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2014
• Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces; environment; Boreal Environment Research
• Online Access: https://hal.science/hal-02957642; https://hal.science/hal-02957642/document; https://hal.science/hal-02957642/file/ber19B-035%281%29.pdf

International audience We aimed to assess the feasibility of an affordable instrumentation, based on a non-disper-sive infrared analyser, to obtain atmospheric CO 2 mole fraction data for background CO 2 measurements from a flux tower site in southern Finland. The measurement period was November 2006-December 2011. We describe the instrumentation, calibration, measurements and data processing and a comparison between two analysers, inter-comparisons with a flask sampling system and with reference gas cylinders and a comparison with an independent inversion model. The obtained accuracy was better than 0.5 ppm. The inter-comparisons showed discrepancies ranging from-0.3 ppm to 0.06 ppm between the measured and reference data. The comparison between the analyzers showed a 0.1 ± 0.4 ppm difference. The trend and phase of the measured and simulated data agreed generally well and the bias of the simulation was 0.2 ± 3.3 ppm. The study highlighted the importance of quantifying all sources of measurement uncertainty.