Abstract:
This presentation will describe a unified approach to land modeling to
enable a controlled and systematic evaluation of multiple model
representations (hypotheses) of physical processes and scaling
behavior. Our approach, which we term the Structure for Unifying
Multiple Modeling Alternatives (SUMMA), formulates a general set of
conservation equations, providing the flexibility to experiment with
different spatial representations, different flux parameterizations,
different model parameter values, and different time stepping schemes.
In this paper, we introduce the general approach used in SUMMA,
detailing the spatial organization and model simplifications, and how
different representations of multiple physical processes can be
combined within a single modeling framework. In particular, we discuss
how SUMMA can help tackle major modeling challenges, including defining
the appropriate complexity of a model, selecting among competing flux
parameterizations, representing spatial variability across a hierarchy
of scales, identifying potential improvements in computational
efficiency and numerical accuracy as part of the numerical solver, and
improving understanding of the various sources of model uncertainty.