Simultaneous monitoring of greenhouse gases and air pollutants in a single instrument

Air pollutants and greenhouse gases (GHG) can be attributed to a variety of sources, such as transportation vehicles and buildings, waste management and agricultural production, natural events such as forest fires and many others. Simultaneous monitoring of air pollutants and GHG with high selectivity and sensitivity enables to detect and evaluate their sources and sinks. Air pollution modelling and validation of emission inventories or satellite observations require measurements at various spatial and temporal scales. 

Infrared laser (IR) absorption spectroscopy offers an efficient way to determine fingerprints of various gas species in monitored air with high precision and reliability. In the past, this technology was commonly used in “one-species-one-instrument” solutions due to limited coverage of used mid-IR distributed feedback quantum cascade lasers (DFB-QCLs). We provide a new compact laser absorption spectrometer that combines several mid-IR lasers. Our solution allows simultaneous high precision measurements of the greenhouse gases CO₂, N₂O, H₂O and CH₄, and the pollutants CO, NO, NO₂, O₃, SO₂ and NH₃ within a single instrument.

In our contribution we will demonstrate examples of our instruments’ applications for mobile monitoring of 10 GHG and air pollutants in urban areas, airborne measurements with airships and measurements at low pollution background stations. Furthermore, we will present the results of parallel monitoring with our instrument and standard conventional gas analysers used for GHG and air pollutant measurements. It demonstrates the ability of our instrument to serve as all-in-one solution and to replace up to 7 standard gas analysers opening a wide range of new mobile multi-compound gas monitoring applications for example in (small) airplanes or cars.