What would happen if an underwater volcano exploded as scientists warn of imminent explosion

A video shows the terrifying reality of what happens if a volcano explodes underwater.

The YouTube channel LifesBiggestQuestions explores what happens when a volcano erupts underwater - and it's both fascinating and a little scary.

We're all familiar with the famously recognised land volcanoes like Eyjafjallajökull and Mt. Krakatau.

But beneath the ocean’s surface, there’s an entire world of submarine volcanoes - one of which is expected to erupt this year!

Submarine volcanoes are underwater vents or fissures in the Earth's crust where magma can erupt.

Most of them are found near tectonic plate boundaries. If you remember geography class in school, tectonic plate boundaries are areas where the Earth’s plates are constantly shifting, creating a lot of tension.

"When these [submarine volcano] things blow and magma reaches the level of the sea floor, it meets the cold water," the video explains.

"And in that moment of primal collision where water meets fire, the magma quickly cools to form basaltic rock."

Pillow lava gets its name from its rounded shape and whitish colour - and it makes up much of the ocean floor.

"If you're ever wondering what the ocean bead is made from, it's primarily that pillow lava," the YouTuber continued.

According to the video, underwater volcanoes function 'exactly the same' as surface volcanoes: "Their tectonic pressure forces forward magma from the Earth's liquid core. It erupts, reacts with water and then forms rock."

But the crazy thing here is that what starts off as a small potential eruption can literally change the world.

In fact, the video warns that 'what can start as a tiny little underwater lava spout could one day become an entire country.'

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If you look at Iceland, the entire country exists because of volcanic activity beneath the ocean, thanks to its location on the Mid-Atlantic Ridge, where the Eurasian and North American tectonic plates meet.

Beneath the Nordic island lies an 'eternally roiling and boiling pot of magma which comprises the very building blocks that created Iceland.'

Away from land creation, these things can also be dangerous to us on the mainland.

In places like the Mediterranean Sea (particularly the Tyrrhenian Sea near Italy) and the Canary Islands, active submarine volcanoes in the surrounding waters can pose serious risks.

Their eruptions can release hazardous materials into the atmosphere, and trigger devastating landslides or even tsunamis during an eruption.

Interestingly, scientists estimate there to be around 40,000 to 55,000 seamounts across global oceans. However, many of these have not yet been identified or even explored.