Happy April Fool’s Day. The ironic thing is that I really am writing about a catastrophic disaster that may happen, just not today. In the Canary Islands, there is a volcano called Cumbre Vieja. During it’s last eruption, the Western flank of the mountain moved about 2 meters towards the sea. If that side of the mountain had actually slid into the Atlantic, a tsunami would have obliterated the East coast of the US a couple hours later.
There is some debate about the danger that Cumbre Vieja’s shifting flank represents. The island moved 2 meters at the surface, but if it’s just a shallow crack, it doesn’t pose much of a threat. If the crack goes deep into the mountain, any eruption could make that part of the island collapse. We just don’t know how deep the crack goes right now.
The volcano is formed in a way that makes it highly unstable. Walls of clay run through the island. Between the inpermeable clays are permeable soils that collect rain that falls on the mountain. As the water builds up in the permeable towers, the pressure increases. A break in the clay walls could lead to an explosive release of steam laterally against the crack that may or may not go all the way through the island.