Extreme Volcanoes takes a good all round look at volcanoes. Here we explain the geology behind eruptions, why, how and where they happen (including on the seabed), and the different types of devastation they can cause: loss of human life, livestock and harvests, damage to homes, transport, communications, the effects depending on the kinds of lava and gases spewed out. We look at weather patterns and temporary climate change, eyewitness accounts and the methods and technology for predicting severe events.