The Tyranny of Small Scales—On Representing Soil Processes in Global Land Surface Models

Abstract

The representation of small-scale soil and hydrological processes has been a challenge and a subject of debate since the pioneering work of Richardson and the dawn of numerical weather prediction. The recent leap to global scales with long-term and large data offers new opportunities that place the long-standing challenge of small-scale representation in a more positive perspective. Global representation of soil processes requires evaluation of the origins of the information used for global models and the parameterization via the so-called pedotransfer functions. Parameters and processes benefit from application of physical constraints while replacing empirical approximations with small-scale physics adapted for large-scale processes. We provide an overview of the present state and opportunities for hydrology and soil communities in contemporary well-connected, observable, global, and big-data realities.