Building and deployment of an automated, in situ greenhouse gas gas chromatographic system.

摘要

High-precision, continuous monitoring of greenhouse gases, such as carbon dioxide (CO2), methane (CH4), nitrous oxide (N 2O), sulfur hexafluoride (SF6), and the criteria pollutant carbon monoxide (CO), is important for characterizing their regional sources and sinks and understanding how their ambient levels are changing with time and associated anthropogenic activities. For monitoring this suite of gases, a fully automated gas chromatographic based analytical system was built and deployed in the field at the UNH AIRMAP Observing Station at Thompson Farm in Durham, NH. The instrument consists of a Shimadzu 17A gas chromatograph (GC), equipped with a Flame Ionization Detector and a custom built methanizer for the measurements of CO2, CH4 and CO; additionally, the GC is equipped with an Electron Capture Detector for measurements of N 2O and SF6. Results from the ambient analyses of this suite of gases provide confidence in the methanizer efficiency, calibration standards and the system's overall performance.