Evaluating performance dependency of a geomorphologic instantaneous unit hydrograph-based hydrological model on DEM resolution

Cheng Yao; Zhi-jia Li; Ke Zhang; Ying-chun Huang; Jing-feng Wang; Satish Bastola

doi:10.1016/j.wse.2022.04.002

Volume 15 Issue 3

Aug. 2022

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Article Navigation > Water Science and Engineering > 2022 > 15(3): 179-188

Cheng Yao, Zhi-jia Li, Ke Zhang, Ying-chun Huang, Jing-feng Wang, Satish Bastola. 2022: Evaluating performance dependency of a geomorphologic instantaneous unit hydrograph-based hydrological model on DEM resolution. Water Science and Engineering, 15(3): 179-188. doi: 10.1016/j.wse.2022.04.002

Citation:

Cheng Yao, Zhi-jia Li, Ke Zhang, Ying-chun Huang, Jing-feng Wang, Satish Bastola. 2022: Evaluating performance dependency of a geomorphologic instantaneous unit hydrograph-based hydrological model on DEM resolution. Water Science and Engineering, 15(3): 179-188. doi: 10.1016/j.wse.2022.04.002

Citation:

Cheng Yao, Zhi-jia Li, Ke Zhang, Ying-chun Huang, Jing-feng Wang, Satish Bastola. 2022: Evaluating performance dependency of a geomorphologic instantaneous unit hydrograph-based hydrological model on DEM resolution. Water Science and Engineering, 15(3): 179-188. doi: 10.1016/j.wse.2022.04.002

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Evaluating performance dependency of a geomorphologic instantaneous unit hydrograph-based hydrological model on DEM resolution

doi: 10.1016/j.wse.2022.04.002

a. College of Hydrology and Water Resources, Hohai University, Nanjing 210098, China;
b. Yangtze Institute for Conservation and Development, Hohai University, Nanjing 210098, China;
c. State Key Laboratory of Hydrology–Water Resources and Hydraulic Engineering, Hohai University, Nanjing 210098, China;
d. China Meteorological Administration–Hohai University Joint Laboratory for Hydrometeorological Studies, Hohai University, Nanjing 210098, China;
e. School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta 30332, USA;
f. Department of Civil and Environmental Engineering, University of New Orleans, New Orleans 70148, USA

Funds:

This work was supported by the National Natural Science Foundation of China (Grants No. 51979070 and 52079035), the National Key Research and Development Program of China (Grant No. 2018YFC1508103), the Natural Science Foundation of Jiangsu Province (Grant No. BK20180022), and the Six Talent Peaks Project in Jiangsu Province (Grant No. NY-004).

Received Date: 2021-10-20
Accepted Date: 2022-03-24
Rev Recd Date: 2022-03-24

Available Online: 2022-08-24

Abstract

Abstract

The digital elevation model (DEM) is a type of model that has been widely used in terrain analysis and hydrological modeling. DEM resolution influences the hydrological and geomorphologic features of delineated catchments and consequently affects hydrological simulations. This study investigated the impacts of DEM resolution on the performance of the XAJ-GIUH hydrological model, a model coupling the widely used Xinanjiang (XAJ) hydrological model with the geomorphologic instantaneous unit hydrograph (GIUH), in flood simulations in small and medium-sized catchments. To test the model performance, the model parameters were calibrated at a fine DEM resolution (30 m) and then directly transferred to the simulation runs using coarser DEMs. Afterwards, model recalibration was conducted at coarser DEM resolutions. In the simulation runs with the model parameters calibrated at the 30-m resolution, the DEM resolution slightly affected the overall shape of the simulated flood hydrographs but presented a greater impact on the simulated peak discharges in the two study catchments. The XAJ-GIUH model consistently underestimated the peak discharges when the DEM resolution became coarser. The qualified ratio of peak simulations decreased by 35% when the DEM resolution changed from 30 m to 600 m. However, model recalibration produced comparable model performances when DEMs with different resolutions were used. This study showed that the impact of DEM resolution on model performance can be mitigated by model recalibration to some extent, if the DEM resolution is not too coarse.
- DEM resolution,
- XAJ-GIUH model,
- Flood simulation,
- Model recalibration,
- Small and medium-sized catchments

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References

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