Volcanic Hazards

Throughout earth’s history volcanoes have been fairly beneficial. Infact they expulsion of Carbon Dioxide in the past allowed the Earth to escape from its Ice Ages which can only be seen as a positive occurrence for everyone living a modern life. Even now a days many countries benefit from volcanic activity such as Iceland which uses the geothermal power, which is easily accessible due to the warm rocks, to provide cheap and plentiful electricity from its country and population. This process benefits not only Iceland economically but the world as a whole as being a renewable and clean source of energy less greenhouse gases are being emitted. Yet it is incredibly important for population living close to active volcanos to remember that if they erupt they are destructive forces with many hazards and risks attached.

A hazard could involve a danger or risk to not only human and animal life but also to shelter, crop production (and therefore the livelihoods of many people) and lastly, on a larger scale, a country's economy. There are numerous possible effects of an eruption and the main hazards include; gas, lahars,landslides, lava flows, pyroclastic flows and tephra. Eruptions from volcanoes can cause some of the biggest changes to societies possible. Immediate effects are those felt by populations near the volcanoes but both the water and land can be altered as far as tens of kilometers from where the eruption occurred. If a supervolcano were to erupt, eg Yellowstone, the impact would be enormous and the repercussions would be felt worldwide, even with a normal volcano just a few liquid drops of sulfuric acid could change the earth’s climate temporarily, with a supervolcano these changes may be permanent.

Some of the first effect of a volcanic eruption are lava flows. These are often seen in Hawaiian type eruptions, volcanic islands formed by hot spots, and mild eruptions - low on the Richter scale usually involving the least explosive type of eruption. With temperatures of higher than 1000C lava flows destroy anything in their past yet as they travel at quite a low speed it's possible for humans and animals to avoid the clutches of the flow. Unfortunately as the direction of the lava flow is very difficult to predict its’ extremely difficult to put preventative measures in place. Therefore lava flows usually damage property as well as any plants or crops in their past. Preparing and planning for the occurrence of lava flows is very difficult. The impacts of these hazards are usually kept quite minimal on a large scale and the only way to stop deal with the lava flow is while the lava is flowing involving either bombing the lava tubes; which create and easy passage for liquid lava to move through. This technique was first used in Hawaii’s Mauna Loa in 1935 and unfortunately failed but new evidence has shown that if the bombs were bigger the technique was likely to have worked. One of the most successful