The degassing of volatile species from the Earth’s interior into the atmosphere has become a rapidly evolving research field. Volatile budgets elucidate geophysical and geochemical processes occurring on geological time scales as volatile species are cycled from the mantle through magmas into the atmosphere and back to the mantle via subduction. Laboratory experiments coupled with modelling allows detailed analysis of volatile source strengths and magma degassing mechanisms, whilst novel field measurement techniques yield insights into the degassing processes observed at the surface. Once emitted into the atmosphere, rapid cooling and mixing with ambient air leads to chemical and meteorological processing of the emitted species. This session will focus on these aspects of volatile degassing. We specifically encourage contributions discussing the application of measurement (both volatiles in magmas and in the air) and modelling studies to attain increased understanding of volcanic and atmospheric processes. In particular, novel applications for volcanic risk assessment and eruption prediction are welcome, as well as studies dealing with the impact of volatile degassing on atmospheric chemistry on local and global scales.