Abstract
Abstract. We present an adapted gas chromatograph capable of measuring simultaneously and semi-continuously the atmospheric mixing ratios of the greenhouse gases CO2, CH4, N2O and SF6 and the trace gas CO with high precision and long-term stability. The novelty of our design is that all species are measured with only one device, making it a very cost-efficient system. No time lags are introduced between the measured mixing ratios. The system is designed to operate fully autonomously which makes it ideal for measurements at remote and unmanned stations. Only a small amount of sample air is needed, which makes this system also highly suitable for flask air measurements. In principle, only two reference cylinders are needed for daily operation and only one calibration per year against international WMO standards is sufficient to obtain high measurement precision and accuracy. The system described in this paper is in use since May 2006 at our atmospheric measurement site Lutjewad near Groningen, The Netherlands at 6°21´ E, 53°24´N, 1 m a.s.l. Results show the long-term stability of the system. Observed measurement precisions at our remote research station Lutjewad were: ±0.04 ppm for CO2, ±0.8 ppb for CH4, ±0.8 ppb for CO, ±0.3 ppb for N2O, and ±0.1 ppt for SF6. The ambient mixing ratios of all measured species as observed at station Lutjewad for the period of May 2007 to August 2008 are presented as well.
Highlights
The effects of Global warming are becoming more and more notable every year
The global average surface temperature has already increased by 0.74◦C between the years 1906 and 2005 (IPCC, 2007)
Most of the observed temperature increase since the mid-20th century can probably be attributed to the observed increase of anthropogenic greenhouse gas mixing ratios (IPCC, 2007)
Summary
The effects of Global warming are becoming more and more notable every year. According to the Intergovernmental Panel for Climate Change (IPCC) eleven of the twelve years between 1995 and 2006 rank among the warmest years since 1850. Our goal was to develop a facility for measuring ambient mixing ratios of the three most important LLGHGs: CO2, CH4 and N2O. This facility was to comply with the following: in-situ measuring the ambient mixing ratios with sufficient temporal resolution (at least several measurements per hour) and a high reliability, low in maintenance, relative easy to operate and autonomously operating. The latter is an essential feature at remote and unmanned stations. We further desired the system to be relatively inexpensive in order to be attractive (cost-benefit wise) for other research groups as well and potentially improve global data coverage
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have