The effects of Pleistocene glaciations on the geohydrological system of Northwest Europe

A large-scale hydrological model study is carried out to investigate the geohydrological responses to glacial climate conditions in Northwest Europe. The vertically integrated groundwater model is based on a supraregional hydrogeological model of the Cenozoic and Mesozoic subsurface in Northwest Europe. Three different layers are distinguished above the relatively impervious base of Palaeozoic and Precambrian rocks. Boundary conditions are inferred from indicative palaeoenvironmental reconstructions of the last three glacial cycles to simulate groundwater flow related to ice sheet expansions into the Northwest European lowlands. Recharge of the groundwater system due to basal glacial melting is deduced from ice sheet model simulations driven by a transient climate function. Results of the large-scale model study show relatively high groundwater velocities and pressures in the subglacial areas and the ice-marginal permafrost areas. Extreme high velocities may develop when the ice sheet has advanced to the southern margins of the upper Plio/Pleistocene aquifer in Northwest Europe. Drainage of the highly pressurized groundwater system mainly occurs in proglacial ice-dammed lakes, ice-marginal seas and zones of discontinuous permafrost, including river valleys. A large-scale hydrological model study is carried out to investigate the geohydrological responses to glacial climate conditions in Northwest Europe. The vertically integrated groundwater model is based on a supraregional hydrogeological model of the Cenozoic and Mesozoic subsurface in Northwest Europe. Three different layers are distinguished above the relatively impervious base of Palaeozoic and Precambrian rocks. Boundary conditions are inferred from indicative palaeoenvironmental reconstructions of the last three glacial cycles to simulate groundwater flow related to ice sheet expansions into the Northwest European lowlands. Recharge of the groundwater system due to basal glacial melting is deduced from ice sheet model simulations driven by a transient climate function. Results of the large-scale model study show relatively high groundwater velocities and pressures in the subglacial areas and the ice-marginal permafrost areas. Extreme high velocities may develop when the ice sheet has advanced to the southern margins of the upper Plio/Pleistocene aquifer in Northwest Europe. Drainage of the highly pressurized groundwater system mainly occurs in proglacial ice-dammed lakes, ice-marginal seas and zones of discontinuous permafrost, including river valleys