Gases (volatiles) in magmatic and hydrothermal systems play a pivotal role in magma transport and drive volcanic eruptions. Changing emissions herald eruptions and document otherwise hidden subsurface changes before, during, and after eruptions. Observatories increasingly monitor gas emissions to track and predict volcano behavior. Scientists research volatiles in magmas and their emissions into the hydro-, atmo-, pedo-, and biosphere, which affect and often dominate the hazard potential on active volcanoes (e.g., slope stability changes,toxic gas accumulations, crop damages). Emissions may be masked by lakes, soil,vegetation, geology, and groundwater, however affected in measurable and often quantifiable ways which offer new approaches to detect and observe current and past activity. Hydrothermal systems mitigate heat and volatile emissions from underlying magmas, potentially affected by changing hydrological conditions in a changing climate. Volcanic gas emission sites are increasingly used as natural analogues to study the effects of rising atmospheric CO₂ levels or leaking geologic CO₂ storage systems, on land and under water.This session aims to mix technical presentations with a strategic discussion on innovation to bolster cross-disciplinary dialogue on monitoring capabilities,and draft a strategic white paper / road map on integrating the competencies presented into a better framework for monitoring volcanic emissions.We welcome contributions from a broad spectrum of expertise, including but not limited to regional and local case studies, mantle and magmatic petrology, hydrothermal geochemistry, volcanic gas investigations, observational and monitoring studies and instrumentation approaches, as well as impacts on aquatic and terrestrial ecosystems, infrastructure, and human health.

Core connection to societal risk mitigation: The emission of gaseous constituents provides for good science, monitoring, and directly impacts vulnerable populations. Emissions from volcanoes before, during, and after unrest periods can be a unique tool for monitoring and eruptive behavior tracking and prediction. The impacts of these emissions on the hydro-, atmo-, pedo-, and biosphere affect and often dominate the hazards potential on active volcanoes (e.g., landslide susceptibility and slope stability change via chemical alteration, dangerous gas accumulations, crop damages, etc.).Understanding and monitoring volatile emissions and the processes they reflect area n underutilized, though essential, part of risk mitigation decision-making strategies.