ABSTRACT

Water cycle has been extensively yet not thoroughly explored because it is closely related to multidisciplines including atmospheric science, meteorology, hydrology, and remote sensing and perplexed by the complexity of the land surface condition and the uncertainty of multisource dataset. With the aid of advanced computing, remote sensing, and Geographic Information System technologies, and available meteorological products with high spatiotemporal resolution, distributed hydrologic models have been rapidly developed and widely used in real-time flood forecasting, near/long-term drought prediction, and general water resources management. In  the past, a hydrologic model focuses primarily on the rainfall infiltration and runoff routing components with a separated land surface model giving the vertical water input. At present, with more frequent interactions among earth sciences, modern distributed hydrologic models usually appear in a more integrated form. Not only a routing model is coupled with a land surface one, ground water and human interference (e.g., irrigation) modules are also introduced to some hydrologic models. In this way, modern hydrologic models play an engine role for many applications in geosciences. In this chapter, we review the evolution of the Coupled Routing and Excess water Storage (CREST) model as an example of a modern integrated hydrologic model.