Continuous Sampling

 In many situations there is a need to study the changes in atmospheric composition with time. We have deployed a number of FTIR systems to measure the important greenhouse gases CO2, CH4 and N2O, as well as CO, a major contributor to air pollution. The picture below shows a prototype system being deployed in the Jenolan Caves, NSW.

 The carbon dioxide (upper trace) and the enrichment of 13C in carbon dioxide observed with this instrument is shown below. Carbon dioxide concentrations vary dramatically during the day, at times when there is no visitors to the cave.