Sunday, January 14, 2007

Living with Volcanoes

Despite the well known hazards associated with volcanic eruptions, it is estimated that 360 million people still live in volcanically active areas. So why do people still live near volcanoes?

Reason: Fertile Soils
Explanation: Volcanic soils are some of the most fertile in the world due to the weathering of volcanic products such as ash lava and rock, which release valuable nutrients and minerals which enrich the soil as well as improving soil characteristics such as moisture retention. In tropical areas in particular, for example Hawaii, climate conditions mean that the weathering of lava etc. is fairly quick resulting in the growth of lush vegetation due to the rapid soil formation. As volcanic areas are therefore ideal for growing crops, they attract large populations.
Example: In Java (Indonesia) some of the best rice growing areas are in the shadow of volcanoes such as Mt Merapi which attract large numbers due to the rich farming opportunities (1 million live within 20 miles of Merapi). Likewise, in Italy large numbers live on the slopes of Vesuvius and Etna (one in five Sicilians are belived to live on the slopes of Etna) due to the fertile soils which provide rich opportunities for growing products such as Olives and fruit.

Reason: Geothermal Energy
Explanation: Heat from magma sources close to the surface in volcanic areas can be used as a source of Geothermal energy which can be harnessed to produce electricity. In these instances, superheated steam, created by the heating of water in permeable rocks in magma can be used to drive turbines. This use of energy is renewable and sustainable, it has the added advantage of being pollution free.
Example: Over 20 countries around the world generate geothermal power, including the US, Italy, New Zealand and Iceland. In fact 17% of Iceland's electricity is created in this way.
In farming areas around Reykjavik (Iceland), geothermal energy is also used to heat greenhouses enabling the growing of fruit, vegetables and flowers.

Reason: Tourism

Explanation: Due to the spectacular scenery associated with volcanic landscapes and unique features such as lava flows and geyers, volcanoes, particularly those having experienced recent eruptive activity are particularly popular with tourists. This is a huge economic benefit due to the resulting multiplier effect. Tourism attracts curstom for businesses such as hotel, cafes etc. creating jobs and improving the local economy.
Example: Yellowstone National Park in the USA with the famous Old Faithful geyser receives around 3 million visitors a year. Iceland is famous for its volcanic landscpae and its hot springs and geysers have attracted many tourists. The Blue Lagoon, near Reykjavik is a spa popular with tourists for its known positive effectives on the skin.

Reason: Minerals
Explanation: Valuable minerals such as copper, gold, silver, lead, zinc and even diamonds are all associated with volanic regions as they are associated with the rising magma which may cool and harden beneath the volcano. As hot water circulate within the cooled magma, the metals are taken by the water and re-deposited in greater concentrations. Thus volcanic areas are excellent areas for mining creating economic activites through job opportunities and the value of the mined minerals.
Example: Copper, Gold and Silver mining began around Mount St Helens as early as 1892.

Reason: Apathy / Unwillingness to Leave Home
Explanation: Due to the infrequency of some volcanic eruptions, some people, particularly those who have not experienced a volcanic eruption in their lifetime are reluctant to leave their homes in order to move to safety and ignore warning, preferring to live with the threat of a volcanic eruption. Some believe that there will be time to move / be resuced should an eruption begin.
Example: Harry Truman was an 83 years old man who lived by Spirit Lake in the Shadow of Mount St Helens. He died in the 1980 eruption due to his failure to heed the warnings of the government and evacuate the area.

Reason: Lack of Choice
It should also be recognised that some people have no choice but to live in these areas. In areas of poverty, people do not have the resources available to move and for many farming on the fertile soils in the shadow of a volcano may be the only livelihood they know.

Follow up Links:
USGS - The "Plus Side" of Volcanoes
Geography Pages - Benefits of Living in Volcanic Areas (thanks to Alan Parkinson)

Photo Source: USGS

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