A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. The process is called Volcanism and has been ongoing on Earth since the initial stages of its evolution over 4 billion years ago.

Body:

Constructive effects of volcanic eruptions:

• Global Cooling:
  • Volcanoes help cool off the earth removing heat from its interior.
  • They play a vital role in periodically cooling off the planet.
  • When volcanic ash and compounds like sulfur dioxide are released into the atmosphere, it can reflect some of the Sun’s rays back into space, thereby reducing the amount of heat energy absorbed by the atmosphere.
  • This process, known as “global dimming”, therefore has a cooling effect on the planet.
• Formation of new landforms:
  • Volcanic landforms are divided into extrusive and intrusive landforms based on weather magma cools within the crust or above the crust. Rocks formed by either plutonic (cooling of magma within the crust) or volcanic (cooling of lava above the surface) are called ‘Igneous rocks’.
  • Volcanoes make islands and add to the continents. It can create new land for human habitation. For example, new island formed in the South Pacific due to Hunga Tonga volcano eruptions.
• Geothermal energy:
  • The heat trapped in the heart of the volcanoes can be utilised as geothermal energy to produce electricity.
• Hot Springs:
  • Hot springs are now being used for supplying hot water in various buildings in New Zealand and Iceland. They are also used for the generation of electricity. Water from hot springs is used for treating skin ailments.
• Outgassing and Atmosphere formation:
  • Volcanoes are a very important source of life. Volcanic emissions have produced the atmosphere and the water of the oceans. This has been happening for 4.5 billion years
• Formation of Fertile Soils:
  • Volcanic soils are fertile, rich in minerals and very good for agriculture. In India, such soil type is referred as Black soil, which is mainly concentrated in the Deccan plateau for cotton cultivation.
• Source of Precious stones and Minerals:
  • Volcanic eruptions sometimes result in the formation of precious stones like the diamond mines Kimberley in South Africa. Many minerals are also found in the volcanic region like copper deposits in Butte in USA.
  • Most of the metallic minerals mined in the world, such as copper, gold, silver, lead, and zinc, are associated with magmas found deep within the roots of extinct volcanoes.
• Provides useful materials:
  • Volcanic eruptions provide useful igneous rocks such as granite and basalt. Both granite and basalt are highly used in construction projects.
• Abrasives:
  • Pumice and volcanic ash are used as abrasives, mostly in hand soaps and household cleaners. The finest grades are used to finish silverware, polish metal parts before electroplating, and for woodworking.
• Volcano Tourism:
  • Fireworks from active volcanoes draw several tourists from different parts of the world and make the volcanic island a popular tourism spot.

Destructive effects of the volcanoes:

• Natural disasters:
  • Volcanic eruptions can cause earthquakes, fast floods, mud slides, and rock falls.
• Lahars:
  • It is a type of mudflow or debris flow that contains magma, minerals and water.
  • During volcanic eruption such mud flows in the surrounding region and has devastating impacts on villages, towns and environment.
• Nuée ardentes:
  • These are dense clouds of hot ash and poisonous gases that are ejected from a volcano. Such volcanic clouds travel at very high speed and to long distances. These cause serious atmospheric disturbances to aircrafts movement.
• Environmental damage:
  • Ash discharged very high into the stratosphere can have negative consequences on the ozone layer.
  • Volcanic eruption releases poisonous atmospheric gases such as carbon monoxide and sulphur dioxide.
  • Lava can travel very far and burn, bury, or damage anything in its path, including people, houses, and trees.

Conclusion:

A volcano eruption is one of the most impressive events in the planet and the effects of volcanoes and their eruptions could be felt as far away as a different continent. The type of effects of volcanoes depends on the size of the eruption.