Continuous methane concentration measurements at the Greenland Ice Sheet-atmosphere interface using a low-cost low-power metal oxide sensor system

• Main Authors: Jørgensen, Christian Juncher, Mønster, Jacob, Fuglsang, Karsten, Christiansen, Jesper Riis
• Format: Text
• Language: English
• Published: 2019
• Subjects: Greenland; Ice Sheet
• Online Access: https://doi.org/10.5194/amt-2019-468; https://www.atmos-meas-tech-discuss.net/amt-2019-468/

In this paper, the performance of a low-cost and low-power methane (CH 4 ) sensing system prototype based on a metal oxide sensor (MOS) sensitive to CH 4 is tested in a natural CH 4 emitting environment at the Greenland Ice sheet (GrIS). We investigate if the MOS could be used as a supplementary measurement technique for monitoring CH 4 emissions from the GrIS with the scope of setting up a CH 4 monitoring network along the GrIS. The performance of the MOS is evaluated on basis of parallel measurements using a CRDS reference instrument for v over a field calibration period of approximately 100 h. Results from the field calibration period show that CH 4 concentrations measured with the MOS is in very good agreement with the reference CRDS. The absolute concentration difference between the MOS and the CRDS reference values within the measured concentration range of approximately 2–100 ppm CH 4 were generally lower than 5 ppm CH 4 , while the relative concentration deviations between the MOS and the CRDS were generally below 10 %. Calculated mean bias error for the entire field calibration period was −0.05 ppm with a standard deviation of ± 1.69 ppm (n = 37 140). The results confirms that low-cost and low-power MOS can be effectively used for atmospheric CH 4 measurements under stable water vapor conditions. The primary scientific importance of the study is that it provides a clear example on how the application of low cost technology can enhance our future understanding on the climatic feedbacks from the cryosphere to the atmosphere.