1. Volcanoes and society

2. Location Usually at plate boundaries At hot spots The ring of fire is the coastal regions around the pacific ocean where plates are moving, creating volcanoes.

3. Risks Ash and tephra Rocks Sun is blocked out. Climatic changes Pyroclastic flows Lahars Earthquakes Lava

4. Volcanic ash and gasses SO 2 Sulfur dioxide, is a deadly gas. CO 2 Carbon dioxide. Water vapor (HOT). Tiny molten silica (glass). Ash consists of tiny jagged pieces of rock and glass. Ash is hard, abrasive, mildly corrosive, conducts electricity when wet, and does not dissolve in water. Ash is spread over broad areas by wind.

5. Bombs and other debris LARGE objects usually really hot thrown from volcano.

6. Flows and Lahars Pyroclastic flows are fast-moving current (450mph) of superheated (1400 o F) Lahars are mudslides created when ice is melted from the eruption and flows down the slope.

7. Earthquakes Before an eruption earthquakes increase in size and numbers.

8. Climate changes The ash and debris from the eruption is shot into the upper atmosphere (50 miles!) and the winds carry that ash around the world. Lowers temperatures (blocks out the sun), and creates storm systems.

9. Prevention No real accurate prevention. When the pressure builds it will release it somehow.

10. Predictions Can we predict, Yes. It is like predicting the weather! Scientists use earthquake swarms to predict a possibility of an eruption. The lava dome inside the volcano is observed, if it builds then pressure is increasing.

11. Protection Knowledge! The land around the volcano is very fertile, but unpredictable. Know routes out of the area. Have a plan. Have a supply kits in the home. If it happens and your in the way most likely there isn't much you can do.

12. Major past events 1980 Mt. St Helens (Washington,USA) 2010 Eyjafjallajökull (Iceland) 1991 Mt. Pinatubo (Philippines) 1982 El Chicho (Mexico) 1883 Krakatoa (Indonesia) 1815 Tambora (Indonesia) 1630 BC Santorini (Greece) 79 AD Vesuvius (Italy)