At a Glance
Simulating the complex interactions between surface and subsurface processes is important for capturing the influence of groundwater storage and flows on land surface processes and associated land-atmosphere fluxes. Most current land surface models, however, employ only simple formulations of shallow, unconfined groundwater storage changes and cannot represent deep aquifers or lateral flows. These shortcomings limit the physical realism of simulated land surface states and fluxes and the characterization of hydrologic extremes. Further, the lack of detailed subsurface process representation in land surface models has limited the utility of data assimilation systems that ingest observations from gravimetry missions such as GRACE and GRACE-FO. This research will leverage the advanced land surface modeling and data assimilation features of the NASA Land Information System (LIS) and the sophisticated subsurface modeling features of ParFlow to develop a next-generation surface-subsurface terrestrial modeling environment that will overcome these limitations and enable new science.