Evaluation of Reliable Digital Elevation Model Resolution for TOPMODEL in Two Mountainous Watersheds, South Korea

Abstract

This study analyzed the result of parameter optimization using the digital elevation model (DEM) resolution in the TOPography-based hydrological MODEL (TOPMODEL). Also, this study investigated the sensitivity of the TOPMODEL efficiency by applying the varying resolution of the DEM grid cell size. This work applied TOPMODEL to two mountainous watersheds in South Korea: the Dongkok watershed in the Wicheon river basin and the Ieemokjung watershed in the Pyeongchang river basin. The DEM grid cell sizes were 5, 10, 20, 40, 80, 160, and 300 m. The effect of DEM grid cell size on the runoff was investigated by using the DEM grid cell size resolution to optimize the parameter sets. As the DEM grid cell size increased, the estimated peak discharge was found to increase based on different parameter sets. In addition, this study investigated the DEM grid cell size that was most reliable for use in runoff simulations with various parameter sets in the experimental watersheds. The results demonstrated that the TOPMODEL efficiencies in both the Dongkok and Ieemokjung watersheds rarely changed up to a DEM grid-size resolution of about 40 m, but the TOPMODEL efficiencies changed with the coarse resolution as the parameter sets were changed. This study is important for understanding and quantifying the modeling behaviors of TOPMODEL under the influence of DEM resolution based on different parameter sets.

Recent Advances in Geographic Information System for Earth Sciences

“…However, TOPMODEL is affected by the resolution of the DEM used. A reliable DEM grid-size resolution that exhibits low sensitivity to changes in input parameters during runoff simulations is investigated by Park et al [9]. A case study in the Dongkok and Ieemokjung watersheds in South Korea shows that the efficiency of TOPMODEL rarely changes up to a DEM grid-size resolution of approximately 40 m, but changes more noticeably with coarser resolution.…”

A Generalized Multistep Dynamic (GMD) TOPMODEL

“…Dynamic‐TOPMODEL of Beven and Freer (2001) relaxed both of the above assumptions by allowing subsurface storage of individual HSUs to vary locally and independently of both the catchment average storage and TI, by incorporating a time‐dependent kinematic wave solution to the subsurface flow. However, since its introduction 20 years ago, and despite significantly improving catchment representation, the original steady‐state version has remained the preferred choice (albeit sometimes with modifications/improvements) (Arenas‐Bautista et al., 2018; Fu et al., 2018; Gil & Tobón, 2016; Jeziorska & Niedzielski, 2018; J. Wang et al., 2020; Lane & Milledge, 2013; Li et al., 2019; Mukae et al., 2018; Park et al., 2019; Rogelis et al., 2016; Xue et al., 2018; Zhang et al., 2016). Aside from the considerable additional complexity in numerical implementation of the dynamic versus the steady‐state version, the lack of momentum in transitioning is most likely due to the substantially slower runtimes, making the dynamic version much less attractive for calibration purposes.…”

Evaluation of Hydrological Simulation in a Karst Basin with Different Calibration Methods and Rainfall Inputs

“…Compared with the traditional lumped hydrological models, the distributed hydrological models particularly consider the inhomogeneity of the underlying surface and rainfall distribution; therefore, the hydrological process in the basin can be reflected more accurately and thoroughly. Typical distributed hydrological models commonly used in hydrological simulation include the SWAT (Soil and Water Assessment Tool) model [1,2], TOPMODEL (Topographic Driven model) [3,4], SHE (System Hydrologique European) model [5,6], VIC (Variable Infiltration Capacity) model [7,8], etc. Since the SWAT model is considered to have a strong physical foundation, it has been widely used to research water-resource management [9], hydrological impacts under a changing environment [10], and non-point source pollution [11].…”