Gudmundsson et al. (2025) Past and future change in global river flows

Identification

• Journal: Nature Reviews Earth & Environment
• Year: 2025
• Date: 2025-12-16
• Authors: Lukas Gudmundsson, Manuela I. Brunner, Petra Döll, Etienne Fluet-Chouinard, Natalia Frolova, Simon N. Gosling, Yukiko Hirabayashi, Maria B. Kireeva, Xiaomang Liu, Hannes Müller Schmied, Dmitriy Magritskiy, Louise J. Slater, Lina Stein, Yves Tramblay, Kaiwen Wang, Conrad Wasko, Dai Yamazaki, Xudong Zhou
• DOI: 10.1038/s43017-025-00745-z

Research Groups

• Institute for Atmospheric and Climate Sciences, ETH Zürich, Zurich, Switzerland
• WSL Institute for Snow and Avalanche Research SLF, Davos Dorf, Switzerland
• Climate Change, Extremes and Natural Hazards in Alpine Regions Research Center CERC, Davos Dorf, Switzerland
• Institute of Physical Geography, Goethe University Frankfurt, Frankfurt am Main, Germany
• Senckenberg Leibniz Biodiversity and Climate Research Centre (SBiK-F), Frankfurt am Main, Germany
• Earth System Science Division, Pacific Northwest National Laboratory, Richland, WA, USA
• Hydrology Department, Faculty of Geography, Lomonosov Moscow State University, Moscow, Russia
• School of Geography, University of Nottingham, Nottingham, UK
• Department of Civil Engineering, Shibaura Institute of Technology, Tokyo, Japan
• Center for Information Technologies, BioSense Institute, Novi Sad, Serbia
• Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
• School of Geography and the Environment, University of Oxford, Oxford, UK
• Institute of Environmental Science and Geography, University of Potsdam, Potsdam, Germany
• Institute for Environmental Science, RPTU University Kaiserslautern-Landau, Landau, Germany
• Espace Dev, Univ. Montpellier, IRD, Montpellier, France
• School of Civil Engineering, The University of Sydney, Sydney, New South Wales, Australia
• Institute of Industrial Science, The University of Tokyo, Tokyo, Japan
• Institute of Hydraulics and Ocean Engineering, Ningbo University, Ningbo, China

Short Summary

This review synthesizes the current understanding of past and projected changes in global river flow, revealing that anthropogenic climate change is a significant driver of observed regional trends (e.g., increased flows in high-latitudes, decreased in mid-latitudes/subtropics, earlier seasonal flows in snow-dominated regions), with these changes projected to intensify. It highlights the complex interplay of climate change and direct human interventions, emphasizing the need for improved monitoring, modeling, and attribution frameworks.

Objective

• To summarize the current understanding of past and projected changes in global river flow, focusing on annual volumes, seasonal dynamics, and sudden changes.
• To identify knowledge gaps and future research needs for improved monitoring, modeling, and robust attribution frameworks to support water resource management, ecosystem sustainability, and climate adaptation.

Study Configuration

• Spatial Scale: Global, with regional analysis focusing on high-latitude, mid-latitude, subtropical, and snow-dominated regions.
• Temporal Scale: Past decades (e.g., 1971–2020 for observed trends) and future projections (e.g., for 1.5 °C and 3 °C global warming scenarios, 21st century).

Methodology and Data

• Models used: Synthesis of findings from various climate models (e.g., CMIP5, CMIP6), global hydrological models (GHMs), and land surface models. Specific models mentioned in contributions include CaMa-Flood and WaterGAP v2.2e.
• Data sources: Review of studies utilizing river flow observations (e.g., Global Runoff Data Centre), satellite data (e.g., GRACE), reanalysis products (e.g., ERA5), and climate model outputs (CMIP5, CMIP6).

Main Results

• River flow observations show distinct regional trends: increased flows in high-latitude regions and decreased flows in parts of the mid-latitudes and subtropics.
• Snow-dominated regions exhibit shifts in their seasonal cycle towards earlier flows.
• These observed patterns broadly align with historical climate model simulations, indicating an anthropogenic climate change signal.
• Attribution of changes is complicated by the combined effects of greenhouse gas emissions, CO₂-driven vegetation response, land-use change, and water management.
• Future projections suggest continued changes, with some regions experiencing wetter conditions and others intensified drying.
• Seasonal changes, particularly those driven by altered snow dynamics, are expected to intensify.
• Significant uncertainties persist regarding the combined impacts of anthropogenic climate change and direct human interventions in terrestrial systems.

Contributions

• Provides a comprehensive review and synthesis of the current state of knowledge on global river flow changes.
• Consolidates evidence for the anthropogenic climate change signal in observed river flow trends.
• Highlights the complex interactions between climate change and direct human activities (e.g., land use, water management) in shaping river flow regimes.
• Identifies critical gaps in monitoring, modeling, and attribution frameworks, outlining future research priorities.
• Offers a typology of changes in river flow and illustrates processes and drivers influencing river flow.

Funding

• European Union’s Horizon Europe research programme (SPARCCLE, no. 101081369)
• Swiss National Science Foundation (A2H2C2, no. IZCOZ0213313; PZ00P2201818)
• Japan Society for the Promotion of Science (JSPS)
• Alexander von Humboldt Foundation (Alexander von Humboldt Professorship endowed by the German Federal Ministry of Education and Research (BMBF))
• UKRI (no. MR/V022008/1)
• NERC (no. NE/S015728/1)
• University of Sydney Horizon Fellowship
• US Department of Energy, Office of Science, Office of Biological and Environmental Research, Environmental System Science (ESS) Program (River Corridor Scientific Focus Area (SFA) project at Pacific Northwest National Laboratory (PNNL))
• Pacific Northwest National Laboratory (Battelle Memorial Institute for the US Department of Energy under Contract DE-AC05-76RL01830)

Citation

@article{Gudmundsson2025Past,
  author = {Gudmundsson, Lukas and Brunner, Manuela I. and Döll, Petra and Fluet-Chouinard, Etienne and Frolova, Natalia and Gosling, Simon N. and Hirabayashi, Yukiko and Kireeva, Maria B. and Liu, Xiaomang and Schmied, Hannes Müller and Magritskiy, Dmitriy and Slater, Louise J. and Stein, Lina and Tramblay, Yves and Wang, Kaiwen and Wasko, Conrad and Yamazaki, Dai and Zhou, Xudong},
  title = {Past and future change in global river flows},
  journal = {Nature Reviews Earth & Environment},
  year = {2025},
  doi = {10.1038/s43017-025-00745-z},
  url = {https://doi.org/10.1038/s43017-025-00745-z}
}