Undersea waterfall dwarfs any on land

The world's largest waterfall is the Denmark Strait cataract, an underwater cascade between Greenland and Iceland.

It carries about 3.5 million cubic metres (3.5 billion litres) of water per second, dwarfing any surface waterfall.

Cold, dense water from the Nordic Seas sinks beneath warmer Atlantic water, flowing down the seafloor over a 2.4-kilometre drop.

The cascade is invisible at the surface but plays a crucial role in driving global ocean currents and climate.