Li et al. (2026) Divergent responses of streamflow reanalysis errors to precipitation reanalysis errors modulated by catchment heterogeneity

Identification

• Journal: Hydrology and earth system sciences
• Year: 2026
• Date: 2026-09-30
• Authors: Qiang Li, Tongtiegang Zhao, Zexin Chen, Zeqing Huang
• DOI: 10.5194/hess-30-6115-2026

Research Groups

• Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Civil Engineering, Sun Yat-Sen University, Guangzhou, China
• Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, New Territories, Hong Kong SAR, China

Short Summary

This paper investigates how streamflow reanalysis errors respond to precipitation reanalysis errors across different catchments. The results demonstrate that the responses are modulated by catchment heterogeneity, with streamflow errors being more directly associated with precipitation errors under saturation-excess conditions and soil moisture deficits dampening their effects.

Objective

• To compare the performance of GloFAS-ERA5 v2.1 and v4.0 in terms of streamflow reanalysis errors.
• To quantify the responses of streamflow reanalysis errors to precipitation reanalysis errors across different catchments.
• To analyze the influence of catchment attributes on these responses.

Study Configuration

• Spatial Scale: Global, with a focus on 671 catchments in the contiguous United States.
• Temporal Scale: Daily time series from January 1940 to the present.

Methodology and Data

• Models used: GloFAS-ERA5 v2.1 and v4.0, as well as the OS LISFLOOD hydrological model.
• Data sources: ERA5 precipitation and temperature reanalysis, Daymet observations, CAMELS dataset for streamflow observations.

Main Results

• The median RMSE of streamflow reanalysis errors decreases from 2.16 to 1.81 mm when upgrading from GloFAS-ERA5 v2.1 to v4.0.
• A significant positive correlation is observed between streamflow and precipitation reanalysis errors in 567 (85% of 671) catchments.
• The coefficient of precipitation error for the random-effects panel regression is 0.51, indicating that a 1 mm increase in precipitation RMSE is associated with an average increase of 0.51 mm in streamflow RMSE.

Contributions

• This study provides a valuable diagnostic method and practical guidance for applications of global streamflow reanalysis to complex, heterogeneous catchments.
• The findings highlight the importance of considering catchment heterogeneity when analyzing the responses of streamflow reanalysis errors to precipitation reanalysis errors.

Funding

• Not specified in the provided text.

Citation

@article{Li2026Divergent,
  author = {Li, Qiang and Zhao, Tongtiegang and Chen, Zexin and Huang, Zeqing},
  title = {Divergent responses of streamflow reanalysis errors to precipitation reanalysis errors modulated by catchment heterogeneity},
  journal = {Hydrology and earth system sciences},
  year = {2026},
  doi = {10.5194/hess-30-6115-2026},
  url = {https://doi.org/10.5194/hess-30-6115-2026}
}