Earth’s surface and shallow (<~100 m) subsurface environment, comprising air, water, biota, organic matter, and Earth materials, encompass the “critical zone”, the dynamic interface between the atmosphere, biosphere, hydrosphere, and lithosphere. While it is straightforward to characterize topography and the above-ground structure of the critical zone, limited direct observations make near-surface geophysics essential to mapping and monitoring below-ground critical zone architecture. Furthermore, their wide range of applicability in terms of scale of measurement (cm to km), makes these methods particularly versatile. In this session we request abstracts focusing on: 1) geophysical characterization/imaging of subsurface critical zone architecture; and/or 2) geophysical monitoring of critical zone processes/dynamics and their interaction with hydrological and biogeochemical cycles. Laboratory to field-based studies spanning from single-point to larger scale measurements (e.g., aerial surveys) with implications for monitoring of critical zone processes in the subsurface, are of particular interest. Studies linking scales of measurement also encouraged.