There has been important progress over the last decade in the theoretical development and validation of models using scaling properties to represent various geophysical processes in general, and hydrological ones in particular. Many of these processes are highly nonlinear and intermittent over a wide range of physical scales.

This session is intended to take stock of the current status of modeling concepts and techniques that address explicitly the multiscale character of geophysical processes at the various scale-ranges (e.g. transport processes at the complex land-air or air-sea interface). Of particular interest is the role of scaling phenomenologies and dynamic down- or up-scaling techniques in formulating subgrid parameterizations. The session will also address the current status of multiphysics parameterizations, when many altogether different processes (with possibly very different scaling properties) need to be combined in simplified descriptions at various scales. Contributions reporting theoretical, numerical, and field or laboratory experimental results are welcome.