There are three motivations to study volcanic degassing: 1) scientific curiosity - it is interesting by itself to learn about the composition of these plumes and to study the (compared to “usual” atmospheric chemistry) very “strange” chemical processes during the evolution of such a plume from emission at the crater until it blends into the atmospheric background. 2) Volcanic gas emissions influence the atmosphere in a number of ways and on different time scales. 3) The composition of volcanic gases gives hints on processes occurring in the Earth’s interior, in particular on magma composition and on degassing processes.
Degassing occurs during magma ascent and depressurization from depth to the surface and has a profound effect on whether the release of magma is explosive or effusive. Even during quiescent periods volcanoes can release large amounts of volatiles. Thus, monitoring of the degassing process constitutes a powerful tool for the surveillance of volcanoes. Further volatiles emitted into the atmosphere, cool rapidly and mix with ambient air, which partly leads to their chemical transformation and therefore interesting atmospheric chemistry.
This session will focus on all aspects of volatile degassing. We specifically encourage contributions discussing measurement (particularly, fumaroles and plumes) and modeling studies to attain better understanding of volcanic and atmospheric processes. In particular, novel applications for volcanic risk assessment and eruption prediction are welcome, as well as flux estimations and studies dealing with the impact of volatile degassing on atmospheric chemistry on local and global scales.