Evaluation of the Uncertainties of Continuous Measurement for Methane in the Atmosphere
CUI Hu-xiong1,CHAI Wen-xuan2,WANG Ying3,FU Qing-yan1
1. Shanghai Environmental Monitoring Center, Shanghai 200235, China
2. China National Environmental Monitoring Centre, Beijing 100012, China
3. Shanghai Chemical Environmental Protection Monitoring Station, Shanghai 200050, China
Abstract：The global climate change caused by the increase of methane concentration in the atmosphere has become a hot spot in the world. In order to accurately study the variation of methane concentration in the atmosphere, it is extremely important to understand and master the uncertainty of methane measurement. On-line gas chromatography is used to measure methane in the atmosphere, the main sources of uncertainty in the measurement process are analyzed, and each uncertainty component is quantified and evaluated. The results show that the expanded uncertainty is 100nmol/mol(k=2, P=95%) when methane concentration is 2000nmol/mol. According to the analysis, it is found that the uncertainty of online measurement of methane in the atmosphere are mainly introduced by the dilution and preparation of standard gases and the fitting of standard curves
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CUI Hu-xiong,CHAI Wen-xuan,WANG Ying,FU Qing-yan. Evaluation of the Uncertainties of Continuous Measurement for Methane in the Atmosphere. Acta Metrologica Sinica, 2023, 44(8): 1293-1297.
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2023, Vol. 44 
