Water shapes the Earth system in all its states: liquid in aquifers, soils, peatlands, rivers, lakes, and oceans; ice in glaciers and permafrost; and vapor in geothermal, hydrothermal, and volcanic systems. Its phase, distribution and movement influence the mechanical properties of the subsurface and are therefore imprinted on how seismic waves propagate. This makes seismology a powerful, non-invasive tool to quantify where water is stored, how it moves, and how it changes phase, across scales from pores to catchments, from the near surface to the deep crust, and from hours to decades.

This session focuses on seismic approaches that image and monitor water, and translate seismic observables into hydrological, cryospheric and fluid-related information. We welcome theoretical, laboratory and field contributions using active and passive methods, including ambient noise, velocity changes, attenuation, dense nodal arrays and distributed acoustic sensing. Themes include groundwater storage and aquifer dynamics, soil moisture and the critical zone, peatland water tables and gas content, glacial hydrology and subglacial and englacial drainage, permafrost and freeze-thaw cycles, crustal fluids in geothermal reservoirs and in hydrothermal systems at volcanoes, and the role of changing hydrological conditions in preconditioning mass movements and other geohazards.

We especially encourage interdisciplinary studies that integrate seismic results with hydrological models, in-situ measurements and remote sensing. Our aim is to bring together seismologists, hydrologists, cryosphere scientists and researchers studying geothermal and volcanic fluids to build a quantitative, physically grounded picture of water in the Earth system.