Why the science of tides was crucial for D-Day : Short Wave

The science of tides shaped one of World War II's defining moments, as planners timed the Normandy invasion to align landing conditions with tidal heights. In 1944, Allied forces needed to assemble tens of thousands of troops off the coast of France and move them ashore overnight across the English Channel, a task made possible by accurate tidal forecasts. Normandy's tide range runs about 20 feet from low to high, a swing large enough to widen beaches by hundreds of yards or expose landing craft to danger if misjudged. NOAA oceanographer Gregory Dusek emphasizes that getting the tides wrong could have derailed the operation, underscoring how tidal science supports coastal defense and disaster planning. The article then explains the mechanics of tides: the Moon and Sun pull on Earth's oceans, creating bulges that produce high tides and low tides as the planet rotates beneath them. As each bulge passes a coast, residents experience a high tide, followed by a low tide. NOAA notes that tides influence shipping, fishing, and flood risk, and that forecasts are increasingly capable of predicting inundation up to a year in advance. While D-Day remains the iconic example, tidal science underpins infrastructure protection and climate resilience worldwide, shaping decisions from ports to flood defenses.