气候变化领域集成服务门户(CCPortal): On the dynamic nature of hydrological similarity

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DOI	10.5194/hess-22-3663-2018
	On the dynamic nature of hydrological similarity
	Loritz R.; Gupta H.; Jackisch C.; Westhoff M.; Kleidon A.; Ehret U.; Zehe E.
发表日期	2018
ISSN	1027-5606
起始页码	3663
结束页码	3684
卷号	22 期号:7
英文摘要	The increasing diversity and resolution of spatially distributed data on terrestrial systems greatly enhance the potential of hydrological modeling. Optimal and parsimonious use of these data sources requires, however, that we better understand (a) which system characteristics exert primary controls on hydrological dynamics and (b) to what level of detail do those characteristics need to be represented in a model. In this study we develop and test an approach to explore these questions that draws upon information theoretic and thermodynamic reasoning, using spatially distributed topographic information as a straightforward example. Specifically, we subdivide a mesoscale catchment into 105 hillslopes and represent each by a two-dimensional numerical hillslope model. These hillslope models differ exclusively with respect to topography-related parameters derived from a digital elevation model (DEM); the remaining setup and meteorological forcing for each are identical. We analyze the degree of similarity of simulated discharge and storage among the hillslopes as a function of time by examining the Shannon information entropy. We furthermore derive a "compressed" catchment model by clustering the hillslope models into functional groups of similar runoff generation using normalized mutual information (NMI) as a distance measure. Our results reveal that, within our given model environment, only a portion of the entire amount of topographic information stored within a digital elevation model is relevant for the simulation of distributed runoff and storage dynamics. This manifests through a possible compression of the model ensemble from the entire set of 105 hillslopes to only 6 hillslopes, each representing a different functional group, which leads to no substantial loss in model performance. Importantly, we find that the concept of hydrological similarity is not necessarily time invariant. On the contrary, the Shannon entropy as measure for diversity in the simulation ensemble shows a distinct annual pattern, with periods of highly redundant simulations, reflecting coherent and organized dynamics, and periods where hillslopes operate in distinctly different ways. We conclude that the proposed approach provides a powerful framework for understanding and diagnosing how and when process organization and functional similarity of hydrological systems emerge in time. Our approach is neither restricted to the model nor to model targets or the data source we selected in this study. Overall, we propose that the concepts of hydrological systems acting similarly (and thus giving rise to redundancy) or displaying unique functionality (and thus being irreplaceable) are not mutually exclusive. They are in fact of complementary nature, and systems operate by gradually changing to different levels of organization in time. © Author(s) 2018.
语种	英语
scopus关键词	Catchments; Digital instruments; Digital storage; Dynamics; Geomorphology; Information theory; Runoff; Spatial distribution; Surveying; Digital elevation model; Hydrological modeling; Meteorological forcing; Modeling environments; Normalized mutual information; Shannon information entropy; System characteristics; Topographic information; Information use; catchment; climate forcing; compression; digital elevation model; discharge; hillslope; hydrological modeling; parameterization; runoff; spatial distribution; spatial resolution; thermodynamics
来源期刊	Hydrology and Earth System Sciences
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/159980
作者单位	Loritz, R., Karlsruhe Institute of Technology (KIT), Institute of Water and River Basin Management, Karlsruhe, Germany; Gupta, H., University of Arizona, Department of Hydrology and Atmospheric Sciences, Tucson, AZ, United States; Jackisch, C., Karlsruhe Institute of Technology (KIT), Institute of Water and River Basin Management, Karlsruhe, Germany; Westhoff, M., Vrije Universiteit, Department of Earth Science, Amsterdam, Netherlands; Kleidon, A., Max Planck Institute for Biogeochemistry, Jena, Germany; Ehret, U., Karlsruhe Institute of Technology (KIT), Institute of Water and River Basin Management, Karlsruhe, Germany; Zehe, E., Karlsruhe Institute of Technology (KIT), Institute of Water and River Basin Management, Karlsruhe, Germany
推荐引用方式 GB/T 7714	Loritz R.,Gupta H.,Jackisch C.,et al. On the dynamic nature of hydrological similarity[J],2018,22(7).
APA	Loritz R..,Gupta H..,Jackisch C..,Westhoff M..,Kleidon A..,...&Zehe E..(2018).On the dynamic nature of hydrological similarity.Hydrology and Earth System Sciences,22(7).
MLA	Loritz R.,et al."On the dynamic nature of hydrological similarity".Hydrology and Earth System Sciences 22.7(2018).