A new model of world rivers

GRIT remaps the world’s rivers, branching into the unknown to aid global flood modelling. A team, led by Professor Louise Slater in the School of Geography and the Environment, has created the most complete map of the world’s rivers ever made offering a major leap forward for flood prediction, climate risk planning, and water resource management in a warming world. The new study, published in Water Resources Research, introduces GRIT—a mapping system that finally shows how rivers really flow, branch, and connect landscapes. Rivers support life—but they also pose growing risks. As rainfall becomes more erratic and sea levels rise, floods are expected to become more frequent and severe in many parts of the world. Yet existing global river maps are outdated and overly simplified, assuming that rivers flow in a single direction and never split. They often overlook complex features, such as when a single river channel splits into multiple channels. These branching river systems are important because they are often found in densely populated, flood‐prone regions, and they are crucial for understanding water movement across the Earth's surface. To address this limitation of existing river maps used for water management and flood prediction, the team have developed a new global river network called Global RIver Topology (GRIT), which includes these branching rivers and large canals, capturing the complexity. GRIT was created by combining high‐resolution satellite imagery of rivers with advanced elevation data of the earth's surface. GRIT not only includes the main river channels but also provides information on river flow directions, widths, and points where rivers split. The GRIT river network has a total length of 19.6 million km and includes 67 thousand bifurcations. GRIT stands to significantly enhance applications in hydrology, ecology, geomorphology, and flood management. For more information visit: https://www.geog.ox.ac.uk/news/grit-remaps-worlds-rivers-branching-unknown-aid-global-flood-modelling Find out more: https://www.ox.ac.uk Latest news and events: https://www.ox.ac.uk/news-and-events Apply to study at Oxford: https://www.ox.ac.uk/admissions/undergraduate Apply for graduate study at Oxford: https://www.ox.ac.uk/admissions/graduate Applying for continuing education courses at Oxford: https://www.ox.ac.uk/admissions/continuing-education Follow Oxford University Twitter: https://twitter.com/UniofOxford Facebook: https://www.facebook.com/the.university.of.oxford Instagram: https://www.instagram.com/oxford_uni/ LinkedIn: https://www.linkedin.com/school/oxforduni/ Medium: https://medium.com/oxford-university Weibo: http://e.weibo.com/OxfordUni