Volcanoes Facts for Kids
Explosive facts about volcanoes and geology
The Mid-Atlantic Ridge, a huge underwater mountain chain running down the centre of the Atlantic Ocean, is constantly producing new ocean floor through volcanic activity. Iceland is the only place where this ridge rises above sea level.
Large volcanic eruptions can temporarily cool the climate by injecting sulphur dioxide into the stratosphere, where it forms tiny droplets that reflect sunlight back into space. This natural cooling effect can last for one to three years after a major eruption.
The ancient Romans built temples and offered sacrifices to gods associated with volcanoes, believing the eruptions were expressions of divine power. They called the volcanically active Phlegraean Fields near Naples 'the entrance to the Underworld'.
Scientists use satellites to track volcanic ash clouds from space, which is vital for aviation safety. When Iceland's EyjafjallajΓΆkull volcano erupted in 2010, its ash cloud forced the cancellation of over 100,000 flights across Europe.
Sulphur dioxide is one of the most dangerous gases released by volcanoes β it can react with water in the atmosphere to form sulphuric acid rain and cause severe respiratory problems for people living nearby. Volcanoes release millions of tonnes of sulphur dioxide into the atmosphere every year.
Mount Rainier in Washington State, USA, is considered one of the most dangerous volcanoes in the world because it is covered in glaciers and close to large cities. If it erupted, the melting ice and snow could generate devastating mudflows reaching all the way to Puget Sound.
Volcanoes are a natural source of carbon dioxide, which has helped regulate Earth's climate over geological time. However, human activities now release about 100 times more carbon dioxide than all the world's volcanoes combined.
When thick lava flows cool slowly and evenly, they can crack into remarkable hexagonal columns called columnar basalt. The Giant's Causeway in Northern Ireland is a famous example and is a UNESCO World Heritage Site.
Many scientists believe that life on Earth may have first emerged near hydrothermal vents on the ocean floor β cracks in the seabed where volcanic heat warms mineral-rich water. These environments could have provided the energy and chemicals needed for the first living cells.
Venus is the most volcanically resurfaced planet in the inner solar system, with its surface almost entirely covered in volcanic plains and thousands of ancient volcanic features. Scientists believe Venus may still have active volcanoes today.