Once a day, a wave as tall as the Empire State Building and as much as a hundred miles wide forms in the waters between Taiwan and the Philippines and rolls across the South China Sea – but on the surface, it is hardly noticed.These daily monstrosities are called “internal waves” because they are beneath the ocean surface and though scientists have known about them for years, they weren’t really sure how significant they were because they had never been fully tracked from cradle to grave.But a new study, published this week in Nature Research Letter, documents what happens to internal waves at the end of their journey and outlines their critical role in global climate. The international research project was funded by the Office of Naval Research and the Taiwan National Science Council.