The Beach That Breathes With the Bay of Fundy’s Giant Tides

Takeaway: At this Bay of Fundy beach, the tide pushes seawater through the sand and gravel like a giant rinse cycle, sending it back to the coast in less than a day.Some coasts don’t just meet the ocean at the surface; they exchange water underground, tide after tide. This episode visits Advocate Beach in Nova Scotia, on the Bay of Fundy, where some of the world’s largest tides push seawater into a steep sand-and-gravel beach and pull it back out through the seabed. That hidden circulation can move nutrients and chemicals into coastal waters, shape shoreline ecosystems, and change how scientists think about beaches in a warming, changing coastal world.We unpack how researchers measured submarine groundwater discharge using seepage meters, radon and radium tracers, and water-level physics; why this mega-tidal beach showed very high discharge rates; and why most of the water was not fresh groundwater from land, but seawater rapidly recycled through the beach in less than a day.Citation: Craddock, R. D., Mohammed, A. A., Tamborski, J. J., & Kurylyk, B. L. (2024). Submarine Groundwater Discharge at a Mega-Tidal Beach. Hydrological Processes, 38, e15319. https://doi.org/10.1002/hyp.15319Disclosure: This Waterlines episode package is written from the cited paper and is designed for production with AI-generated voices.