What is like living near a volcano? What is it like most of the time? What happens when it erupts?

Why do people live near volcanoes? At first it may seem odd that people would want to live close to a volcano or any tectonic activity. After all, volcanoes have a nasty habit of exploding, discharging liquid rock, ash, poisonous gasses, red hot clouds of embers, and generally doing things that kill people. Yet, throughout history, people have deliberately chosen to risk all those hazards and live near them, even on the slopes of active volcanoes that have erupted within living memory.

They chose to live close to volcanoes because they felt that the advantages outweighed the disadvantages. Most volcanoes are perfectly safe for long periods in between eruptions, and those that do erupt more frequently are usually thought of, by the people who live there, as being predictable. Today, about 500 million people live on or close to volcanoes. We even have major cities close to active volcanoes. Popocatapetl is a volcanic mountain less than 50 miles from Mexico City in Mexico. In short, the main things that attract people to live near active volcanoes are minerals, geothermal energy, fertile soils and tourism. Lets look at each one...

These are the countries we are going to mention today – do you know which they are?

Geothermal Energy Geothermal energy means heat energy from the earth. It's unusual to use the heat directly, by building your house on top of a steam vent for example, because it's unpredictable, dangerous and messy. The heat from underground steam is used to drive turbines and produce electricity, or to heat water supplies that are then used to provide household heating and hot water. Where steam doesn't naturally occur it is possible to drill several deep holes into very hot rocks, pump cool water down one hole and extract steam from another hole close by.

Geothermal Energy Countries such as Iceland make extensive use of geothermal power, with approximately two thirds of Iceland's electricity coming from steam powered turbines. New Zealand and to a lesser extent, Japan, also make effective use of geothermal energy. Iceland has over 200 volcanoes and 800 hot springs 26% of Iceland’s electricity comes from Geothermal Power. Reykjavik is said to be “the most unpolluted capital in Europe.” It’s true - the city is absolutely pristine. The air is crystal clear. The geothermal electricity generation has a lot to do with this.

Other uses of Geothermal power in Iceland It is also used for recreational purposes Blaa Lonio - The Blue Lagoon. In the middle of this huge lava field sits this pool of seawater naturally heated by the geothermal activity below the surface. Southeast of Reykjavik, the town of Hveragerdi serves as a geothermal farming centre for the capital. Puffs of steam coming out of the ground all over the place. There were greenhouses everywhere, often surrounded by steaming cracks in the ground. The extreme climate of Iceland is actually able to produce much in the way of tropical fruits and vegetables with the help of geothermal steam.

Fertile Soils Volcanic rocks are rich in minerals, but when the rocks are fresh the minerals are not available to plants. The rocks need thousands of years to become weathered and broken down before they form rich soils. When they do become soils though, they form some of the richest ones on the planet. The Naples area, which includes Mount Vesuvius, has such rich soils thanks to two large eruptions 35,000 and 12000 years ago. Both eruptions produced very thick deposits of ash and broken rocks which have weathered to rich soils. Today, the area is intensively cultivated and produces grapes, vegetables, orange and lemon trees, herbs, flowers and has become a major tomato growing region

Tourism creates a lot of jobs Volcanoes attract millions of visitors every year, for different reasons. As an example of the wilder side of nature, there are few things that can beat seeing an erupting volcano blowing red hot ash and rock thousands of feet into the air. Even the less active ones that are just puffing out steam and smoke are impressive sights and attract tourists from around the world. Around the volcano may be warm bathing lakes, hot springs, bubbling mud pools and steam vents. Geysers are always popular tourist attractions, such as Old Faithful in the Yellowstone National Park, USA. Old Faithful is such a popular tourist feature that it even has its own 24 hour Old Faithful webcam. In Uganda, a country trying hard to increase its tourist industry, the volcanic region around Mt Elgon is being heavily promoted for it's landscape, huge waterfalls, wildlife, climbing and hiking and its remote 'get away from it all' location. This one is in New Zealand

They stay there because there is nowhere else to go – it is home Land is cheap in volcanic and earthquake zones. Some people are too poor to leave their home (especially in LICs) – also poor education does not explain why they should move further away Even when people can afford to leave the area they may be too attached to their homes to leave. Their families have been there for generations. And there are so many people living in these dangerous areas, that it would difficult if not impossible to re-house them, especially as many areas that provide food for so many other people.

So living near a volcano can have its advantages, but how do you cope with the danger? Scientists can often find clues about past eruptions by studying the deposits left behind. Areas affected by lava flows etc can be mapped, making disaster planning more effective. In addition to this type of long-range forecasting, scientists are becoming more and more skilled at spotting the warning signs of an eruption.

Warning Signs Before an eruption, magma moves into the area beneath the volcano and collects in a magma chamber, or reservoir. As it comes closer to the surface, the magma releases gases. These events can offer valuable clues about the likelihood of an eruption. For example, the movement of magma produces small earthquakes and vibrations Magma gathering in a chamber causes slight swelling of the volcano's slopes. Gases released near the volcano can be measured for changes in quantity and makeup.

A really helpful diagram

Monitoring Methods A number of tools can be used to record these warning signs. Seismographs can detect small earthquakes, while tiltmeters and geodimeters can measure the subtle swelling of a volcano. Spectrometers can measure amounts of sulfur dioxide a telltale gas that is released in increasing quantities before an eruption. Using these and other tools, it's possible to closely monitor activity at an awakening volcano. Volcanologists are becoming very skilled at predicting the likelihood of an eruption.

But …. ……. it's very difficult to pinpoint exactly when an eruption will happen. Often, moving magma doesn't result in an eruption at all, but instead cools below the surface. Monitoring potential eruptions is expensive. With many volcanoes erupting only every few hundred or thousand years, it's not possible to monitor every site. Volcanic eruptions don't occur without warning, however. If we set up monitoring devices, we should not be caught off guard by disastrous eruptions.

So an eruption occurs – what are your chances? Depends where you live

Most Likely to …. be in an HIC or LIC (or maybe both??) Imagine 2 eruptions from composite volcanoes that have thrown out a large amount of ash and lava and been explosive – one in an HIC and one in an LIC. In which these are these incidents mostly likely to happen? All the buildings in the area are check annually to make sure their structure is safe. This area has only a few people living there. They choose where to put their houses carefully, so as not to be in the path of lava. This is a densely populated area. The soil is so good, so that farmers only need a small amount of land to feed their families, so there are lots of them. Houses are dotted everywhere There has not been a major volcanic eruption for 60 years. Many buildings are made of wood and have corrugated roofs The area has an Area Disaster Management Office, to take charge in the event of any unforeseen event

Most Likely to …. be in an HIC or LIC (or maybe both??) The area does not have a full time fire or ambulance service, and the hospital is 50 km away – the only way there is a bus Sometime the volcano sends out puff of ash but no-one takes much notice The volcano is constantly monitored for bulges and emissions of gas. Most houses have a metal box, in which they kept important papers, a cash card, spare medicine. They also had a suit case with a set or 2 of clothes for everyone. Most homes did not have any idea what to do if there was an eruption As a result of monitoring, a yellow warning was issued. The locals smelt gas and wondered if this might mean trouble was on the way. There was widespread TV coverage of a small bulge in the side of the volcano Every household was supplied with a safe route out if they needed to evacuate.

Most Likely to …. be in an HIC or LIC (or maybe both??) The radio gave out messages and police on motorbikes came round with loud hailers telling people to leave. Arrangements were made for the old and disabled, both with transport out and a centre to go to. Everyone was told using TV, internet and local press to leave as the ash clouds increased in number. Most people packed up their cars with valuables and left. Those that could not drive were collected by social workers. Most people packed up what they could carry and moved down the mountain. If they were lucky they may sleep in a tent the next night. Some people did not want to leave their homes. Ash and lava covered the whole area. There were no deaths and only a few people ended in hospital with breathing difficulties. Many 1000s of flimsy houses were destroyed by the lava or squashed flat by the weight of ash falling on them.

Most Likely to …. be in an HIC or LIC (or maybe both??) Many 1000s of flimsy houses were destroyed by the lava or squashed flat by the weight of ash falling on them. Many houses only received slight damage as very few were built in the known path of lava down the mountain. There were a few that would have to be rebuilt. It is believed that most people got away, but a few hundred had stayed as they thought it would be OK – it wasn’t. The ash got them and most suffocated. There were quite a few injuries, falls, breathing problems, but some died of them as there were not enough doctors or supplies for everyone. The electric was down and some water supplies were off, but within 3 weeks it was all back on. The wells became polluted and what with that and the lack of feed for the animals most of them died. Most people were back in their homes in a month. Those that did return were in tents for months while they tried to rebuild their homes. Many did not return but went to live in the city.

So what are your conclusions? In an HIC? In an LIC?

So you are living in a volcanic zone? What can you do to stay safe?

Your plan should include 4 parts What do I need to know and have ready in case an eruption should happen? What will I do if an eruption is predicted? What will I do during an eruption? What will I do after an eruption?

OK – you live in a volcanic area What do you need to know and have ready in case an eruption should happen?

Suggestions include Learn about your community warning systems. Be prepared for these disasters that can be spawned by volcanoes. Earthquakes, Flash floods, Landslides and mudflows, Thunderstorms, Tsunamis Make evacuation plans. You want to get to high ground away from the eruption. Plan a route out and have a backup route in mind. Develop an emergency communication plan. In case family members are separated from one another during a volcanic eruption, have a plan for getting back together. Ask an out-of-state relative or friend to serve as the "family contact." Make sure everyone knows the name, address, and phone number of the contact person. Have disaster supplies on hand. Flashlight and extra batteries, Portable, battery-operated radio and extra batteries, First aid kit and manual, Emergency food and water, Non-electric can opener, Essential medicine, Cash and credit cards, Sturdy shoes, A pair of goggles and a throw-away breathing mask for each member of the household.

The volcano alert has been made TV and Radio are telling people to evacuate URGENTLY The eruption could be any time soon! You have a plan – but what could go wrong with it?

Some ideas Although it may seem safe to stay at home and wait out an eruption, doing so could be very dangerous. The rock debris from a volcano can break windows and set buildings on fire. Stay safe. Follow authorities' instructions and leave the area before the disaster begins. Follow the evacuation order issued by authorities. - Avoid areas downwind of the volcano. Mudflows or Lahars : are powerful "rivers" of mud that can move faster than people can walk or run and occur when rain falls through ash-carrying clouds or when rivers are dammed during an eruption. When you approach a bridge, first look upstream. If a mudflow is approaching or moving beneath the bridge, do not cross the bridge. The power of the mudflow can destroy a bridge very quickly.

If eruption happens before you get away If caught indoors: Close all windows, doors, and dampers. Put all machinery inside a garage or barn. Bring animals and livestock into closed shelters. If trapped outdoors: Seek shelter indoors. If caught in a rock fall, roll into a ball to protect head. Avoid low-lying area where poisonous gases can collect and flash floods can be most dangerous. If caught near a stream, beware of mudflows. Protect yourself: Wear long sleeved shirts and pants. Use goggles to protect eyes. Use a dust-mask or hold a damp cloth over face to help breathing. Keep car or truck engines off.

Afterwards Listen to a battery-powered radio or television for the latest emergency information. Stay away from volcanic ash fall. When outside: Cover your mouth and nose. A number of victims of the Mount St. Helens volcano died from inhaling ash. Wear goggles to protect your eyes. Keep skin covered to avoid irritation or burns. If you have a respiratory ailment, avoid contact with any amount of ash. Stay indoors until local health officials advise it is safe to go outside. Avoid driving in heavy ash fall. Driving will stir up more ash that can clog engines and stall vehicles. Clear roofs of ash fall. Ash fall is very heavy and can cause buildings to collapse.

Homework Imagine you are an advertising executive and you want to attract people to visit or live on your volcano (you might like to use your volcano from last week?) In a 3-slide PowerPoint Explain why it is really the one place they would like to come to how they will protected by monitoring how they can prepare to survive any disaster Keep it brief and punchy – this is an advert remember – Don’t let the font size go below size 24