Aquatic-terrestrial interfaces such as hyporheic zones, riparian corridors, wetlands, lake margins, and permafrost-affected regions connect surface and subsurface systems through exchanges of water, solutes, and energy, shaping elemental cycling and water quality across Earth’s landscapes. This session invites contributions that advance mechanistic and predictive understanding of coupled surface and subsurface flow, reactive transport, and biogeochemistry across aquatic-terrestrial interfaces through diverse and complementary approaches. We particularly encourage studies where models, observations, and experiments iteratively inform one another: data constrain model parameters and structure, and models identify process gaps that motivate new measurements. Contributions may include long-term monitoring, laboratory and mesocosm experiments, isotopic and geochemical tracers, geophysical subsurface characterization, process-based multiphysics modeling, physics-informed machine learning and hybrid modeling frameworks, surrogate and emulator models for uncertainty exploration, digital twins with real-time data assimilation, and transferable models trained across multiple sites.

• B - Biogeosciences
• C - Cryosphere
• EP - Earth and Planetary Surface Processes