Monday, March 15, 2010

Natural Disasters – Volcanoes

One of the most visually impressive natural disasters is volcanoes. Volcanic eruptions can send burning lava, ashes and fire through the air. Some of the dangers from a volcano are Pyroclastic bombs. A volcano can send balls of molten lava for great distances that can kill people suddenly far away from a volcanic eruption. They can be hurled over 10 miles from a volcano, killing people and starting fire to buildings. The heat from a volcano can cause snow and ice on a volcano to melt very fast and create a landslide of water, mud, rock and volcanic ash, this is often called lahars. A volcano sometime created a cloud of hot gases and pulverized volcanic rock that can travel at very high speeds down from a volcano destroying everything that it affects, this is often called pyroclastic clouds. This is one of the major dangers from a volcano and is a danger that it very hard to escape if you still find yourself in proximity to a volcano in case of an eruption. The gas that’s emitted from a volcano can both be irritating but can reach a concentration so high that it can be lethal. In some cases a major volcanic eruptions can cause devastating tsunamis that can kill people far away from the eruption. Ashes from volcanoes can severely damage infrastructure and block roads, airports, rivers and railways.

Timeline
79 The volcano Vesuvius in Italy had a devastating eruption. The two roman cities Pompeii and Herculaeum was destroyed and it is estimated that as many as 25.000 may have died in the eruption. Pyroclastic flows, lava and volcanic ashes destroyed the towns. Some of the skeletons found in Herculaeum have been found buried with the former inhabitants frozen in positions from their everyday work. This is one of the most famous volcanic eruptions in history.

1792 Unzen in Japan had a devastating eruption that resulted in a tsunami killing more than 15.000 people. This is one of the worst disasters in Japanese history.

1821 A devastating eruption took place on Iceland. The eruption covered over 500 square kilometers with lava and enormous amounts of gases and volcanic ash affected large parts of northern Europe. A large number of cattle died and famine followed. Around 20% of the Islands 50.000 inhabitants died from the following famine. A previous large eruption had taken place 1612.

1883 The Volcanic eruption on Krakatau in Indonesia resulted in the deaths of 35.000 to over a 100.000 people from both the direct effects and a devastating tsunami that was created by the explosive eruption that could be heard for over 3.000 km away. The Tsunami devastated many islands and coastal areas, none of the around 3.000 people living on the Island Sebesi survived.

1902 Mont Pelee in the Caribbean had a devastating eruption. The eruption caused a pyroclastic cloud that totally destroyed the city of Saint-Pierre and it was first sad that only two persons in the city that had around 30.000 inhabitants survived. Many wounded died later from the burns contracted by the pyroclastic cloud.

1980 Mount St Helens in the state of Washington had a devastating eruption that released as much energy as a 24 megaton nuclear weapon. The volcano lost 400m in height from the eruption that killed 62 people, two of them volcanologists. There was also extensive damage to the infrastructure in the area and road was blocked from the volcanic ashes released from the eruption. The area surrounding the volcano had been evacuated, a action that seriously reduced the loss of human lives.

1982 a volcanic eruptions at El Chichon in Mexico created a pyroclastic cloud that traveled downwards from all sides of the volcano and destroyed a number of villages, killing around 2000 people.

1985 the Nevado Del Ruiz volcanic eruption resulted in around 24.000 dead in Colombia. The Volcano melted ice and snow that resulted in devastating lahars that hit the areas and valleys surrounding the volcano. The lahars almost completely destroyed the city of Armero and more than half of the population was killed. A similar outbreak in the same location had taken place in 1895.

1986 in Cameron, Africa 1700 died after the volcanic activity at the Lake Nyos released high amounts of Gas. A high number of life stock died as well but there was no physical destruction like usually is associated with volcanic eruptions.

1991 The Japanese Volcano Unzen had another eruption that resulted in around 40 deaths.

1993 Galeras in Colombia had a sudden small eruption that resulted in the deaths of 6 scientists and 3 tourists.

2002 Mount Nyiragongo in Zaire, Africa had a eruption that sent lava flows through the city Goma. 45 died and over 100.000 homeless became homeless.

2010 A large volcanic eruption from a volcano under the glacier Eyjafjallajokull on Iceland has created a large cloud of volcanic ash that has resulted in severe problems for air traffic in large parts of Europe.

Risk and Survival
Volcanic eruptions is unpredictable events that can take place after thousands of years giving residents that surround them a sense of false security. If you live near a volcano I suggest you should take actions to understand the different kinds of risks that you may be facing. What history does the volcano have and what has these events resulted in? How are warnings given from local government agencies? Most volcanoes in the world are monitored by experts so eruptions can often be foreseen and the areas evacuated.

It’s very hard to shield from the devastating effects that a volcano can create so it is very important that you leave the area if you are in the proximity of a volcano when a warning about coming eruptions is given. It is common that people instead move to the area in order to see the visual effects of the eruption and thereby putting themselves in harm’s way. Volcanologists may often provide information that saves others but they are a group that especially find themselves at risks and deaths are common. Always takes warning serious and don’t wait to evacuate.

· During an evacuation scenario a Bug Out Bag or Get Home Bag can be useful tools to help you deal with this type of situation.

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