Andrew’s research focuses on improved understanding of the storage, transport and exchange of fluids within the subsurface environment. Early work targeted the modelling of rainfall runoff processes, which led to the Generalised Likelihood Uncertainty Estimation (GLUE) methodology (Beven and Binley, 1992) for model uncertainty estimation. This triggered his research path in hydrogeophysics, with a core aim of exploiting data rich geophysical techniques for constraining the uncertainty in hydrological models. He has developed and applied geophysical approaches to a wide range of groundwater-related problems from lab- to field-scale. An active theme of his research over the past 20 years is the exchange of groundwater and surface water through fundamental, process-based investigations. These studies have often been driven by the need to understand the fate of legacy nitrate in groundwater. This work has been complemented by a parallel theme on the assessment of large-scale vadose zone nitrate storage and delivery to deep groundwater. Past research also includes the investigation of plant-soil-water interactions – this includes geophysics-based phenotyping of plant root function and the influence of root development on soil hydraulic properties. To exploit the potential of geophysics, Andrew has worked on the development of new methods for data assimilation and inverse modelling. He was written (and made available) several inverse codes for electrical geophysics problems, which continue to be widely used across the world.

His research has been funded by UKRI (NERC, BBSRC and EPSRC), EU, US Dept. Energy, US NSF and various industrial organisations.