The largest waterfall is in the Strait of Denmark. Here a deep sea current passes over a kind of geological threshold at a depth of 600 meters.
The salty, cold water of the sea current is heavier than the surrounding water. The heavier water passes the threshold and falls 3505 meters down to the bottom of the Atlantic.© NOAA
A cold, salty sea stream carries water from the Gulf Stream via a waterfall back to the south.
5 million m3 of water passes through the waterfall per second - 2000 times as much as in the Niagara Falls.