Wang et al. (2025) Impacts of irrigation on hot extreme in the Yangtze River Basin using observed analysis and model simulation

Identification

• Journal: Journal of Hydrology
• Year: 2025
• Date: 2025-09-19
• Authors: Yafei Wang, Pan Liu, Qian Xia, Z. Yun, Weibo Liu
• DOI: 10.1016/j.jhydrol.2025.134271

Research Groups

• State Key Laboratory of Water Resources Engineering and Management, Wuhan University, China
• Hubei Engineering Research Center of Water Resources Digital and Intelligent Technology, Hubei Water Resources Research Institute, China
• CIECC, China

Short Summary

This study investigates the impact of irrigation on hot extremes in the Yangtze River Basin using observational analysis and WRF model simulations, revealing that irrigation reduces extreme high temperatures by an average of 0.3 °C, with a maximum decrease of 1.4 °C, and identifies a threshold for cooling benefits at an irrigated area fraction of 0.3.

Objective

• To assess the impacts of irrigation on hot extremes in the Yangtze River Basin (YRB) of China using two independent methods: observational analysis and the WRF model with an irrigation module, aiming to validate previously simulated irrigation-induced cooling effects.

Study Configuration

• Spatial Scale: Yangtze River Basin (YRB), China
• Temporal Scale: Not explicitly defined in the provided text, but focuses on current impacts and historical observations.

Methodology and Data

• Models used: WRF (Weather Research and Forecasting) model with an irrigation module
• Data sources: Observational analysis (implied from "observed analysis"), Model simulation

Main Results

• Irrigation decreased the average extreme high temperature in the Yangtze River Basin by 0.3 °C.
• The highest observed decrease in extreme high temperature due to irrigation was 1.4 °C.
• A threshold for the cooling benefits of irrigation expansion was identified: cooling intensity increases with the expansion of the irrigated area fraction but diminishes once the fraction exceeds 0.3.
• Irrigation primarily achieves its cooling effect on extreme high temperatures by increasing humidity and latent heat fluxes while reducing sensible heat fluxes.

Contributions

• Provides validation for irrigation-induced cooling effects on hot extremes using both observational analysis and model simulations, addressing a gap in previous studies that relied mostly on unvalidated simulations.
• Quantifies the cooling effect of irrigation on extreme high temperatures in a typical humid/semi-humid region with intensive irrigation (Yangtze River Basin).
• Identifies a critical threshold for the effectiveness of irrigation expansion in mitigating hot extremes.
• Emphasizes the necessity of considering irrigation impacts in future climate predictions and for efficient land management.

Funding

• Not explicitly mentioned in the provided text.

Citation

@article{Wang2025Impacts,
  author = {Wang, Yafei and Liu, Pan and Xia, Qian and Yun, Z. and Liu, Weibo},
  title = {Impacts of irrigation on hot extreme in the Yangtze River Basin using observed analysis and model simulation},
  journal = {Journal of Hydrology},
  year = {2025},
  doi = {10.1016/j.jhydrol.2025.134271},
  url = {https://doi.org/10.1016/j.jhydrol.2025.134271}
}