Despite water vapor in the atmosphere being the most potent greenhouse gas relatively little is known about the physical processes influencing the absolute content in the atmosphere – that being the fluxes between the atmosphere and the biosphere, cryosphere, hydrosphere, and lithosphere, and the processes during cloud and precipitation formation and between boundary layer and free atmosphere. With recent years development in isotope spectroscopy analyzers it is now possible to obtain detailed observations of unprecedented quality and quantity. This facilitates a direct comparison between observations and General Circulation Model outputs as to both validate models and suggest weaknesses in physical parameterizations. These measurements also allow for detailed studies of isolated processes both in the field and in the laboratory. However, this new field is still in need of both instrument improvements as well as standardized measurement protocols. We encourage all contributions in relation to water vapor observations, modeling, and measurement techniques.

This session is co-sponsored by the European Association of Geochemistry