Effects of volcanic activity

POSITIVE

Fertile soils --> Volcanic soils are very fertile. These rich soils are called laterite soils and are rich in minerals. These soils are sometimes called terra rossa. They are common to many countries such as Brazil, where coffee is grown, and parts of southern Italy, where fruit and vegetables are grown.
Tourism --> Many dormant and active volcanoes attract hundereds of thousands of tourists each year. e.g. Mount Vesuvius in Italy and Mount Etna in Sicily. Tourists flock here to climb the sides and experience the landscape. This leads to many spin-off industries such as bus companies, restaurants, shops, souvenir shops, and hotels. This generates a lot of employment. In the case of Mount Vesuvius, nearby locations such as Pompeii, destroyed in 79 AD by the violent eruption of Vesuvius, also attract tourists. Yellowstome National Park, where the Geyser Old Faithful erupts every hour, is also very popular with tourists.
Geothermal energy --> is responsible for providing approximately 80% of homes in Iceland with their electricity. Energy is harnessed in areas where water is superheated to temperatures often over 1000 degrees due to rocks being heated below them. The water does not evaporate but instead the steam and hot water are pushed to the surface where turbines harness the energy produced. This energy is then turned into electricity as is done in Iceland.
Creation of new land --> Volcanoes can create new land for human habitation e.g. Iceland.
Building materials --> Granite, which is used in the construction industry, is formed by volcanic activity.

NEGATIVE

Lahars --> Lahars are formed where ice and snow on top of a volcanic cone melt when an eruption occurs. Theses lahars create mudflows, which can travel down the slopes of a volcanic cone into the surrounding region. This can have devestating effects for towns and villages e.g. Mount Pinatubo in the Philippines.
Nuée Ardentes --> These are clouds of hot ash and poisonous gases that are ejected from a volcano. They create what is sometimes called glowing avalanches. These clouds travel down the volcanic cone sides at huge speeds of up to 200km per hour and can travel great distances.
Loss of life --> The eruption of Mount Vesuvius in 79 AD caused death and destruction. More than 20,000 people died and the towns of Pompeii and Herculaneum were destroyed.
Damage to property --> Lva can burn everything in its path.
Effect on the environment --> Clouds of ash, dust, and gas may reduce global temperatures by several degrees. The emission of sulfur dioxide into the atmosphere may lead to acid rain. Other toxic, poisonous gases such as carbon monoxide and sulfur can also be harmful to humans. In addition pyroclastic material ejected from a volcano can damage the environment e.g. CO2 adds to the greenhouse effect. Sulfur dioxide causes environmental problems as it is converted to sulfuric acid in the stratosphere. This is a major cause of acid rain.

	Created by eimearkelly3 over 11 years ago

Leaving Certificate Geography (The geography of volcanoes) Note on The Geography Of Volcanoes, created by eimearkelly3 on 05/07/2013.