Incorporating groundwater flow in land surface models: literature review and recommendations for further work

HydroJULES is a NERC-funded project that brings together NERC Centre-Surveys to investigate how to improve the simulation of the whole hydrological cycle in models. BGS’ role is to inform the inclusion of groundwater in both the land surface model Joint UK Land Environment Simulation (JULES) (Best et al., 2011; Clark et al., 2011) and the hydrological model Grid to Grid (e.g. Bell at al, 2009). To facilitate this a literature review has been undertaken of the current methods for inclusion of groundwater in land surface models. The keywords ‘global groundwater model’, ‘land surface models’ and ‘parameterisation’/‘parameterization’ were used to search the literature. Further, the main global datasets of relevance to HydroJULES have been summarised. The main finding is that the LEAF-Hydro approach (Miguez-Macho et al., 2007) is one of the most practical methods in the literature for including groundwater simulation in a land surface model. It is recommended that the LEAF-Hydro approach should be tested against existing BGS groundwater flow models for the UK