The IAGOS-Core Greenhouse Gas package : a CO2, CH4, CO and H2O measurement system for deployment on board commercial airliners

Reliable measurement systems are the basis for investigating the temporal and spatial atmospheric distribution of the most significant greenhouse gases and for understanding their budgets, trends and connection to global climate change. Within the framework of the IAGOS project (In-service Aircraft for a Global Observing System) an analyser for the autonomous measurement of the greenhouse gases (GHGs) CO2 and CH4 , as well as CO and water vapour was designed, tested and qualified for deployment aboard passenger aircrafts. It is based on a commercial cavity ring-down spectroscopy (CRDS) instrument which has been modified to meet the specific requirements regarding physical dimensions, automatic and long-term operation and safety issues on board commercial airliners. This work presents results from test flights and laboratory tests that document the performance of the CO2, CH4, CO and water vapour measurements.