CO₂ measurements with an infrared laser spectrometer on flask samples collected at Jungfraujoch high‐altitude research station (3500 meters asl) and with light aircraft up to 8000 meters over Switzerland

We discuss the use of an infrared laser spectrometer for CO 2 concentration analysis of flask samples. The precision of the system is 2.5‰, or 0.75 ppm. A series of monthly measurements at the Jungfraujoch high‐altitude research station, Switzerland (3500 m asl), is discussed together with vertical profiles up to 8000 m asl.