[E] Towards consistent predictions of water and energy cycles in intermediate scale catchments

The main goals of the proposed project are to advance distributed modeling of water-, energy- and mass cycles in intermediate scale catchments (few to few hundred km²) by addressing the following research questions:

• How to balance necessary complexity and parsimony of hydrological models?
• How to compare models of different complexity in a fair manner and which data/information sources are most important to discriminate the structurally most adequate model?

As an important prerequisite to address these questions, our further objective is to improve and provide quantitative rainfall estimates (QPE) adequate for high-resolution modeling on the lower mesoscale.

Additionally we aim on developing a framework for structured and fair model inter comparison using the Attert catchment as test bed and the CAOS, ROGeR, CATFLOW and NOAH-MP model as representative sample of the wide range of structure and process complexity representations in current modeling approaches. We will especially explore the role of quantitative rainfall estimates (QPE) for high-resolution modeling by advancing the methods that have been proposed within phase I project C.

Based on these hypotheses, we will pursue the project goals by further development of the functional core of the CAOS model, further development of the adaptive modeling scheme based on identification of dynamic similarity of model elements, further development and application of a multi-parameter, multi-scale verification concept, improving observation-based QPE methods and by comparing the CAOS model performance to competing model structures on the lower mesoscale.