Towards improved criteria for hydrological model calibration: theoretical analysis of distance- and weak form-based functions

JOURNAL OF HYDROLOGY

卷:401

Article

Guinot, V.¹  Cappelaere, B.¹  Delenne, C.¹  Ruelland, D.¹ 

[1] Univ Montpellier 2, HydroSci Montpellier UMR 5569, CNRS, IRD,UM1,UM2,CC MSE, F-34095 Montpellier 5, France

关键词: Model performance evaluation;    Calibration;    Objective function;    Mean squared error;    Nash-Sutcliffe efficiency;    Conceptual hydrological model;   

DOI  :  10.1016/j.jhydrol.2011.02.004

来源: Elsevier

【 摘 要 】

Calibrating conceptual hydrological models is often done via the optimization of objective functions serving as a measure of model performance. Most of the objective functions used in the hydrological literature can be classified into distance- and weak form-based objective functions. Distance- and weak form-based objective functions can be seen respectively as generalizations of the square error and balance error. An analysis of the objective functions shows that: (i) the calibration problem is transformed from an optimization problem with distance-based objective functions into a root finding problem for weak form-based functions; (ii) weak form-based objective functions are essentially less prone to local extrema than distance-based functions; (iii) consequently, they allow simple gradient-based methods to be used; (iv) parameter redundancy can be assessed very simply by superimposing the contour lines or comparing the gradients of two objective functions of similar nature in the parameter space; and (v) simple guidelines can be defined for the selection of the calibration variables in a conceptual hydrological model. The theoretical results are illustrated by two simple test cases. Weak form-based approaches offer the potential for better-posed calibration problems, through the use of a number of independent criteria that matches the dimension of the identification problem. In contrast with distance-based objective functions, they do not have the inconvenience of solution non-uniqueness. Finally, the need for models with internal variables bearing a physical meaning is acknowledged. (C) 2011 Elsevier B.V. All rights reserved.

【 授权许可】

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