The numerical integration of HBV96 and LARSIM-ME as a source of uncertainty

作者：Tyralla Christoph^*; Schumann Andreas

来源：Hydrologie und Wasserbewirtschaftung, 2014, 58(2): 138-147.

DOI：10.5675/HyWa_2014,2_9

• HBV96
• integration uncertainty
• LARSIM-ME
• numerical integration
• parameter optimization
• simulation uncertainty
• water balance models

In recent years, the analysis of the impact of structural model inadequacies on simulation uncertainty has gained increased attention in hydrological research. One aspect of structural model inadequacy is the imperfect numerical integration of differential equation systems. This aspect is still neglected in many rainfall runoff and water balance models. Often process equations are solved by model-specific"ad hoc"-integration schemes. These are time-efficient but can lead to significant inaccuracies. In this study we examine the "ad hoc" numerical integration schemes of the water balance models HBV96 and LARSIM-ME. Comparisons with a more elaborate integration method suggest that both HBV96 and LARSIM-ME are affected by noticeable integration uncertainty in the calculation of interception. In the other model components this is only the case for LARSIM-ME. The overall integration uncertainty of HBV96 appears to be rather low when it is compared directly to the total simulation uncertainty. One reason for this is its small time-step width compared to the chosen configuration of LARSIM-ME. Whether integration uncertainty leads to severe indirect effects on simulation uncertainty due to artificial irregularities of error hypersurfaces complicating parameter optimization remains to be examined in further studies.

• 出版日期2014-4