Zhou et al. (2026) Threefold increase in atmospheric–riverine compound heatwaves under climate change

Identification

• Journal: Nature Geoscience
• Year: 2026
• Date: 2026-07-30
• Authors: Yu Zhou, Yanxia Shen, Wei Zhi, Bo Zhou, Senlin Zhu, Yuan Li, Yangyang Wang, Chuan Wang, Kun� Shi, Amir AghaKouchak, Michelle T. H. van Vliet, Chunhui Lu, Richard Iestyn Woolway
• DOI: 10.1038/s41561-026-02040-y

Research Groups

• University of California, Berkeley
• University of Colorado Boulder
• National Oceanic and Atmospheric Administration (NOAA)
• European Centre for Medium-Range Weather Forecasts (ECMWF)
• University of Oxford

Short Summary

This study examines the increasing trend of atmospheric-riverine compound heatwaves under climate change. The analysis reveals a threefold increase in such events over the past four decades, with significant impacts on river water quality and aquatic ecosystems.

Objective

• Investigate the spatiotemporal trends and main drivers of atmospheric-riverine compound heatwaves (ARCHs)
• Assess the impact of ARCH events on river water quality compared to isolated RHWs

Study Configuration

• Spatial Scale: Continental-scale analysis across 796 river basins in the USA and Central Europe
• Temporal Scale: Daily data from 1981 to 2019, with future projections under SSP2-4.5 and SSP5-8.5 scenarios

Methodology and Data

• Models used: Deep learning model (LSTM) for reconstructing daily river water temperature and dissolved oxygen records
• Data sources: USGS National Water Information System, NLDAS-2, DAYMET, LamaH-CE dataset, GAGES-II, and national/ regional monitoring agencies in Central Europe

Main Results

• ARCH frequency increased from 0.76 to about 2.3 events per year since the 1980s (+0.40 events per decade)
• RHW duration and intensity increased by 5.92 days per decade and 1.54 °C per decade, respectively
• Compound heatwaves exert a synergistic amplification of water quality deterioration, driving an additional 16% rise in WT and a further 2.9% decline in DO

Contributions

• This study highlights the escalating threats of compound heatwaves to freshwater ecosystems and the need to incorporate their dynamics into future water risk assessments
• The findings suggest that continued warming may drive aquatic systems towards a regime shift, from episodic extremes to chronic thermal stress

Funding

• National Science Foundation (NSF)
• National Oceanic and Atmospheric Administration (NOAA)
• European Research Council (ERC)
• University of California, Berkeley
• University of Colorado Boulder

Citation

@article{Zhou2026Threefold,
  author = {Zhou, Yu and Shen, Yanxia and Zhi, Wei and Zhou, Bo and Zhu, Senlin and Li, Yuan and Wang, Yangyang and Wang, Chuan and Shi, Kun� and AghaKouchak, Amir and Vliet, Michelle T. H. van and Lu, Chunhui and Woolway, Richard Iestyn},
  title = {Threefold increase in atmospheric–riverine compound heatwaves under climate change},
  journal = {Nature Geoscience},
  year = {2026},
  doi = {10.1038/s41561-026-02040-y},
  url = {https://doi.org/10.1038/s41561-026-02040-y}
}