About
The River Experiment (RivEx) is a global research initiative dedicated to advancing our understanding of Earth’s most renewable and accessible freshwater resource: our rivers. While we know that freshwater is essential for life and society, there are surprising gaps in our understanding of how much water is flowing through the world’s rivers and how it’s changing over time.
This is a critical moment for surface water science. With a new generation of satellite missions (e.g. Surface Water and Ocean Topography, Sentinel 3, Sentinel 6 Michael Freilich), global efforts to gather in situ measurements (Global Runoff Data Centre), and advanced numerical models (e.g. CaMa-Flood, CTRIP, HyMAP, LISFLOOD, RAPID), we are poised for a transformation in our ability to observe, simulate, and understand global surface water dynamics.
The RivEx initiative, endorsed as a Cross-Cutting project by the GEWEX Hydroclimatology Panel (GHP), brings together a diverse, international community of scientists to harness this new data. Our goal is to create a common strategy for improving and comparing our hydrological models, ultimately turning advanced global science into actionable knowledge that benefits local communities worldwide.
Our Core Questions
We are a community-driven effort focused on tackling some of the most pressing questions in surface water hydrology today:
- State of the Art: How well can we currently model the world’s rivers, and where do our models succeed or fail?
- Human Fingerprint: What are the hotspots of human influence—from dams to water use—on our rivers, and how can we accurately account for them in our models?
- Data Revolution: How can we best integrate the deluge of new satellite observations together with local observations to create more accurate and reliable predictions of surface water stores and fluxes?
Read more about our project in the first GEWEX quarterly newsletter of 2025.
Get Involved and Collaborate
RivEx is a grassroots effort built on collaboration, open science, and a shared passion for discovery. We welcome the inclusion of all ideas, individuals, and communities. Our strength lies in the diversity of our participants, and we especially encourage the involvement of Early Career Researchers.
We hold quarterly virtual meetings with our entire membership to share progress, exchange ideas, and build consensus. To stay informed about our activities, receive meeting invitations, and join our vibrant community, please sign up for our mailing list.
Sign-Up
If you want to be kept informed about the RivEx Initiative, sign-up for our mailing list by sending a message to the International GEWEX Project Office at contact@gewex.org.
The broad objective of the River Experiment Initiative:
modeling across space and time scales for the benefit of science and society
