Ying et al. (2026) Warming-driven compound floods from extreme temperature and precipitation in global glacier covered areas

Identification

• Journal: Journal of Hydrology Regional Studies
• Year: 2026
• Date: 2026-04-12
• Authors: Bingqi Ying, Qinglai Xiong, Xueping Zhu, Wei Qi, Jing Zhang, Xuehua Zhao, Wenjun Cai
• DOI: 10.1016/j.ejrh.2026.103433

Research Groups

• College of Water Resources Science and Engineering, Taiyuan University of Technology, Taiyuan, China
• Guangdong Basic Research Center of Excellence for Ecological Security and Green Development, School of Ecology, Environment and Ocean, Guangdong University of Technology, Guangzhou, China
• Shanxi Key Laboratory of Collaborative Utilization of River Basin Water Resources, Taiyuan, China

Short Summary

This study investigates how global warming intensifies compound flood hazards in glacier regions by enhancing the temporal synchronization of extreme temperature and precipitation, finding that flood magnitudes can increase by over 60% under 3–4 °C warming, particularly for long-duration events.

Objective

• To assess how extreme precipitation and temperature change across global glacier regions under different warming levels.
• To determine if climate warming enhances the temporal synchronization between extreme precipitation and temperature events, and how this synchronization varies spatially.
• To quantify how changes in synchronization translate into changes in compound flood magnitude and frequency under increasing warming levels.

Study Configuration

• Spatial Scale: Global glacier regions, with specific attention to major high-mountain systems such as the Tibetan Plateau and the Andes.
• Temporal Scale: Four global warming levels (1.5 °C, 2.0 °C, 3.0 °C, and 4.0 °C) relative to a pre-industrial baseline (1850–1900 mean temperature), analyzed over 30-year periods for each warming level.

Methodology and Data

• Models used: An enhanced degree-day model (DDM) incorporating a rainfall–snowmelt coupling mechanism to simulate compound flood runoff. A new timing-based metric, Difference in days between annual maximum Precipitation and Temperature (DPT), was introduced to quantify synchronization.
• Data sources: Bias-corrected climate projections from ISIMIP3b (SSP1-RCP2.6, SSP3-RCP7.0, SSP5-RCP8.5 scenarios) based on an ensemble of five Global Climate Models (GFDL-ESM4, IPSL-CM6A-LR, MPI-ESM1–2-HR, MRI-ESM2–0, UKESM1–0-LL) corrected towards ERA5 (W5E5) observational data. Glacier inventory from the Randolph Glacier Inventory (RGI) and shoreline data from the Global Self-consistent Hierarchical High-resolution Shoreline (GSHHS) dataset.

Main Results

• Global warming intensifies both individual extreme events and their temporal synchronization in glacier regions.
• Median annual maximum temperature is projected to increase from 12.5 °C historically to 17.0 °C under 4.0 °C warming, with annual maximum precipitation increasing by up to 60%.
• The Difference in days between annual maximum Precipitation and Temperature (DPT) decreases by 10–50% globally, and by over 50% in the Tibetan Plateau and Andes, indicating enhanced temporal alignment of extreme heat and rainfall.
• Compound flood magnitudes are projected to increase by over 60% under 3–4 °C warming, with some regions experiencing nearly a doubling, particularly for longer-duration events (5-day and 7-day).
• The frequency of compound floods exceeding historical thresholds is projected to increase substantially, surpassing 200% in multiple regions under 3.0 °C and 4.0 °C warming, reaching 3–4 times historical frequency in some high-risk areas.
• Longer-duration compound floods exhibit a "reduced spatial footprint – heightened intensity" distribution, becoming more concentrated and extreme in energy-intensive glacier regions.

Contributions

• Provides the first global-scale assessment of warming-driven heat–rainfall compound flood dynamics in glacier regions.
• Introduces a novel risk assessment framework specifically adapted for glacier environments, integrating an enhanced degree-day model with a rainfall–snowmelt coupling mechanism.
• Develops and applies a new, physically interpretable index, DPT (Difference in days between annual maximum Precipitation and Temperature), to quantify the temporal synchronization of extreme temperature and precipitation events.
• Offers the first empirical evidence for the amplification of hydrological hazards by compound events in high-altitude and high-latitude glacierized regions.

Funding

• National Natural Science Foundation of China (52379018, U22A20613)
• Central Government Guides Local Science and Technology Development Fund Projects, China (YDZJSX2024D024)
• Shanxi Province Science and Technology Cooperation Project, China (202404041101037)

Citation

@article{Ying2026Warmingdriven,
  author = {Ying, Bingqi and Xiong, Qinglai and Zhu, Xueping and Qi, Wei and Zhang, Jing and Zhao, Xuehua and Cai, Wenjun},
  title = {Warming-driven compound floods from extreme temperature and precipitation in global glacier covered areas},
  journal = {Journal of Hydrology Regional Studies},
  year = {2026},
  doi = {10.1016/j.ejrh.2026.103433},
  url = {https://doi.org/10.1016/j.ejrh.2026.103433}
}