Luo et al. (2025) A framework for assessing the impact trends of neglecting water surface evaporation and substituting streamflow on water budget closure

Identification

• Journal: Journal of Hydrology
• Year: 2025
• Date: 2025-10-10
• Authors: Zengliang Luo, Sihan Zhang, Xiangyi Ding, Lunche Wang, Quanxi Shao, Heqing Huang, Xizhang Chen, Huan Li
• DOI: 10.1016/j.jhydrol.2025.134391

Research Groups

• Hubei Key Laboratory of Regional Ecology and Environmental Change, State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China
• Engineering Research Center of Natural Resource Information Management and Digital Twin Engineering Software, Ministry of Education, Wuhan, China
• State Key Laboratory of Water Cycle and Water Security in River Basin, China Institute of Water Resources and Hydropower Research, Beijing, China
• CSIRO Data61, Australian Resources Research Centre, Kensington, WA, Australia
• State Key Laboratory of Remote Sensing Science, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, China
• HUN-REN Balaton Limnological Research Institute, Hungary

Short Summary

This study introduces a framework to quantify the impact of neglecting water surface evaporation (WSE) and substituting runoff (R) for observed streamflow (Q) on water budget closure across 62 global river basins. It reveals that these practices introduce significant, context-dependent uncertainties, particularly when the water surface area ratio is high or in humid basins.

Objective

• To assess the individual and combined impacts of substituting runoff for streamflow and neglecting water surface evaporation on water budget closure across diverse global river basins.

Study Configuration

• Spatial Scale: 62 river basins worldwide.
• Temporal Scale: Not explicitly stated in the provided text.

Methodology and Data

• Models used: Proportional Redistribution (PR), Constrained Kalman Filter (CKF), Multiple Collocation (MCL), and Minimized Series Deviation (MSD) for water budget closure correction (BCC).
• Data sources: Multiple remote sensing and other datasets for precipitation (P), evapotranspiration (ET), streamflow (Q), and terrestrial water storage change (TWSC).

Main Results

• The impact of neglecting water surface evaporation (WSE) is primarily influenced by the ratio of water surface area to land area within a basin. Errors become non-negligible when this ratio exceeds 9.92%.
• Substituting runoff (R) for streamflow (Q) has a more pronounced effect in humid basins, introducing approximately 11.53% uncertainty, compared to arid basins, where it introduces around 4.13% uncertainty.
• Combined uncertainties from both neglecting WSE and substituting R for Q are higher than those from a single factor alone, especially in basins with a high proportion of water surface area.

Contributions

• Provides a novel framework to systematically assess the impact trends of neglecting WSE and substituting R for Q on water budget closure.
• Quantifies the uncertainties introduced by these common practices, particularly highlighting the role of water surface area ratio and climatic conditions.
• Offers critical insights for improving the reliability of satellite-based water budgeting and hydrological datasets, especially in regions lacking direct observations.

Funding

Not explicitly stated in the provided text.

Citation

@article{Luo2025framework,
  author = {Luo, Zengliang and Zhang, Sihan and Ding, Xiangyi and Wang, Lunche and Shao, Quanxi and Huang, Heqing and Chen, Xizhang and Li, Huan},
  title = {A framework for assessing the impact trends of neglecting water surface evaporation and substituting streamflow on water budget closure},
  journal = {Journal of Hydrology},
  year = {2025},
  doi = {10.1016/j.jhydrol.2025.134391},
  url = {https://doi.org/10.1016/j.jhydrol.2025.134391}
}