Jökulhlaup

Jökulhlaups are huge floods of melting water and ice. They happen when a volcano erupts under a glacier, or when a glacier melts very quickly due to warm weather, like a heat wave. The pressure of all the melting water and ice pushes the water forward, like a big wave. This flood of water carries a lot of dirt and rocks as it moves quickly down the side of a mountain. It can be very dangerous, so it's important to stay away if you know that a jökulhlaup is coming.