tracergasanalyse

Trace gas analysis is the measurement and characterization of gases that occur in very small concentrations in a medium, most commonly the Earth's atmosphere or indoor air. It focuses on detecting and quantifying trace constituents at parts per billion or lower (ppb to pptv), enabling the study of sources, sinks, chemical reactions, and transport processes that influence air quality, climate, and ecosystems.

Analytical approaches combine sampling with sensitive detection. Techniques include mass spectrometry methods such as GC-MS, PTR-MS, and SIFT-MS; optical methods such as Fourier-transform infrared spectroscopy (FTIR), laser-based absorption spectroscopy (including cavity ring-down and cavity-enhanced methods), and photoacoustic spectroscopy; and chromatographic techniques such as GC with various detectors. Isotope-ratio measurements and real-time, in-situ sensors are also common.

Applications span atmospheric science, climate research, and air-quality monitoring; industrial process control and leak detection; agricultural and environmental monitoring; indoor air quality assessments; food, flavor, and fragrance research; and medical breath analysis. Data from trace gas analysis are used to quantify concentrations, emissions, lifetimes, and reaction mechanisms.

Challenges include achieving low detection limits with high selectivity, calibrating instruments across environments, accounting for interferences, and maintaining complex equipment. Ongoing developments aim at portable, real-time sensors, multi-species platforms, and standardized protocols to enable intercomparison of measurements across studies.