Everyone knows the ocean is dangerous, and in almost too many ways to count. From booming storms tossing ships around, massive tsunami racing from fault lines towards the shore, or whirlpools swirling like the flush of a giant toilet bowl, the ocean has claimed countless lives over the course of human history. It’s no wonder that stories of sea monsters have circulated across the globe to serve as cautionary tales for anyone willing to venture out towards the bright, blue, endless horizon.
And those are just the most cinematic dangers. There are also plenty of other, more subtle ways the ocean can get you. The undertow, for instance, is a downward sucking force that happens when water rushes up to a beach and then back out to the ocean, and it’s been known to pull small children under. Rip currents are similar, but are actually waist-to-chest-high waves that don’t break, making their way to shore and then flowing quickly back out to the surf line. Rip tide, as the name says, is a current caused by tidal flow to or from the shore, especially along the edge of an inlet, and the sudden rush of water can be deadly.
But there’s one dangerous ocean phenomenon you’ve probably never heard of even though it’s actually spectacularly weird to behold: cross seas.