Satellites Capture Record-Breaking 20-Metre Waves Crossing Entire Oceans

The biggest ocean swells ever have been captured by satellites, which shows the power of giant waves to transport a storm across oceans as a whole. In another, an open-ocean wave caused by a North Pacific storm (Storm Eddie, Dec 2024) reached a height of almost 65 feet, or 20 meters (almost half the height of the Arc de Triomphe in Paris). These massive waves were capable of covering thousands of miles, and this proved that the power of storms could travel miles to the far coasts and societies, even in cases when the storm does not touch land.

Record-Breaking Storm Waves Observed

According to an ESA report, during recent storms, satellites recorded ocean waves nearly 20 meters high – the largest ever measured from space. For instance, Storm Eddie (December 2024) was a source of a series of water waves in the open ocean, which were close to 20 m (almost 65 feet) high.

The scientists have taken advantage of SWOT's (Surface Water and Ocean Topography) wide-swath radar imaging along with the other satellite data to figure out a "global view" of the storm waves. Those record-breaking swells travelled about 24,000 km from the Pacific to the tropical Atlantic, even though the storm itself remained at sea.

Waves Carry Storm Energy to Shores

Ocean swells (long, rolling waves produced by distant storms) act as “storm messengers,” carrying destructive energy far from a storm's origin. By measuring swells, scientists can infer storm strength and warn distant shores.

For example, researchers observed these far-travelled swells causing erosion and flooding on remote coastlines. For decades, experts assumed very long swells carried most of a storm's energy. The new observations show that much of this energy is actually concentrated in shorter, steeper waves.