Multiscale Problems in Subsurface Hydrology

A broad range of scientific and engineering problems involve multiple scales and multi-scale phenomena. In particular, the physical properties that control many hydrologic subsurface processes vary dramatically over a range of spatial scales. Such heterogeneity occurs in many geological media where depositional processes that act over different characteristic time scales induce spatial patterns having different characteristic spatial scales. In this talk, we focus on flow and transport processes as they take place in the subsurface and discuss coarse scale models derived from a detailed small scale model, bypassing the necessity of empirical modelling and, on the other hand, overcoming the limitations of global homogenization procedures. Employing systematic coarsening procedures that yield models at intermediate scales and resolution will lead us to adaptive coarsening procedures.