- Mention about the Pacific ring of fire (with diagram).
- Discuss its effect on climate & soil.
A volcano is an opening on the surface of a planet or moon that allows material warmer than its surroundings to escape from its interior. When this material escapes, it causes an eruption.
Most volcanoes are concentrated on the edges of continents, along island chains, or beneath the sea forming long mountain ranges. More than half of the world’s active volcanoes above sea level encircle the Pacific Ocean to form the circum-Pacific “Ring of Fire.” Although uncommon, some volcanoes also exist thousands of kilometres away from tectonic plate boundaries which are known as hotspots.
Effect of volcanoes on climate:
Volcanic ash or dust released into the atmosphere during an eruption shade sunlight and cause temporary cooling. Erupting volcanoes emit sulphur dioxide into the atmosphere. The sulphur dioxide moves into the stratosphere and combines with water to form sulfuric acid aerosols. Volcanoes also release large amounts of greenhouse gases such as water vapour and carbon dioxide.
Effect of volcanoes on soil:
Volcanic deposits are enriched in elements such as magnesium and potassium. When volcanic rock weathers, these elements are released, producing extremely fertile soils. Volcanic deposits, particularly ash, are quite porous, retaining moisture longer than many non-volcanic soils. Eruptive products and forces that produce volcanoes shape landscape, sometimes removing land and sometimes adding to it, affecting soil of the area.
Volcanoes are important part of the globally synchronised tectonic activity of the entire planet. Empirical studies in this direction will allow for a better prediction of future volcanic eruptions.