HALVIRE - Trapping a volcanic plume

Within the project HALVIRE (HALogen Activiation in Volcanic plumes In Reaction chamber Experiments) a simplified artificial volcanic plume was created inside a 4000 L Teflon smog chamber located in Bayreuth to investigate the formation of reactive bromine species under different initial conditions such as abundance of SO2, relative humidity, total bromine species and aerosol load. The reactive gas species were detected contact-less by Differential Optical Absorption Spectroscopy (DOAS). A multi reflection cell and 3 optical resonators were used to created folded light paths with total lengths of several 100 to a few kilometers in different spectral ranges. High aerosol load lead to scattering of the light of the DOAS instruments making the absorption paths visible.