Using residual analysis, auto- and cross-correlations to identify key processes for the calibration of the SWAT model in a data scarce region

K. Bieger,G. Hörmann,N. Fohrer

doi:10.5194/adgeo-31-23-2012

Abstract

Abstract. Hydrological modeling poses a particular challenge in data scarce regions, which are often subject to dynamic change and thus of specific interest to hydrological modeling studies. When a small amount of data available for a catchment is opposed by extensive data requirements by the chosen hydrologic model, ways have to be found to extract as much information from the available data as possible. In a study conducted in the Xiangxi Catchment in the Three Gorges Region in China, the use of residual analysis as well as auto- and cross-correlations for enhanced model evaluation and for the identification of key processes governing the hydrological behavior of the catchment prior to model calibration was tested. The residuals were plotted versus various variables such as time, discharge and precipitation. Also, auto-correlations were calculated for measured and simulated discharge and cross-correlations of measured and simulated discharge with precipitation were analyzed. Results show that the analysis of residuals as well as auto- and cross-correlations can provide valuable information about the catchment response to rainfall events, which can be very helpful for calibration of hydrologic models in data scarce regions.

Highlights

In many parts of the world, parameterization and calibration of hydrological models is hampered by a lack of adequate input data (Zhao et al, 2011)
In a study conducted in the Xiangxi Catchment in the Three Gorges Region in China, the use of residual analysis as well as auto- and cross-correlations for enhanced model evaluation and for the identification of key processes governing the hydrological behavior of the catchment prior to model calibration was tested
Results show that the analysis of residuals as well as auto- and cross-correlations can provide valuable information about the catchment response to rainfall events, which can be very helpful for calibration of hydrologic models in data scarce regions

Summary

Introduction

In many parts of the world, parameterization and calibration of hydrological models is hampered by a lack of adequate input data (Zhao et al, 2011) Often it is especially those parts of the world, where dynamic change is currently encountered or expected to happen in the future and where modeling studies estimating the impacts of this change on hydrology and water quality are indispensable. The impact of land use change on the water balance as well as the sediment and phosphorus transport is assessed using the eco-hydrological model SWAT (Arnold et al, 1998). SWAT will be used during further progress of the project to simulate the impact of past, present and future land use patterns on the water balance as well as sediment and phosphorus transport in the catchment.

Methods

Results

Conclusion