VOLCANO - GEOGRAPHY

News: INCOIS keeps watch on Barren-island volcano eruption 

What is in the news?

       The volcano on the Barren Island of the Andaman & Nicobar Islands is being closely watched to check for signs of an eruption which could lead to a tsunami or a monstrous undersea landslide akin to what had happened in Indonesia in 2018.

       The monitoring is being carried out by the Indian National Centre for Ocean Information Services (INCOIS), which houses the Indian Tsunami Early Warning Centre (ITEWC) here.

About Barren-island volcano:

       It is India’s only active volcano.

       It has become active again.

       After lying dormant for 150 years, Barren Island volcano erupted in 1991 and since then it is showing sporadic activity. Now it is erupting in small episodes of five to 10 minutes.

       It is claimed that volcanoes are erupting the rising magma formed deep in the mantle due to the melting of the subducted Indian Ocean crust.

       The volcanic island is part of Andaman Islands. Its northern part is barren and is uninhabited. It is also devoid of vegetation.

       The volcano about 140 km northeast of Port Blair has been emitting smoke and is not capable of causing major destruction.

About Tsunami Early warning system in Indian Ocean:

       The Indian Tsunami Early Warning System (ITEWS) was established in 2007 and is based at & operated by INCOIS, Hyderabad.

       It is an integrated effort of different organizations including the Department of Space (DOS), Department of Science and Technology (DST), the Council of Scientific and Industrial Research (CSIR), Survey of India (SOI) and National Institute of Ocean Technology (NIOT).

       ITEWS comprises a real-time network of seismic stations, tide gauges and a 24X7 operational tsunami warning center to detect tsunamigenic earthquakes, to monitor tsunamis and to provide timely advisories to vulnerable communities.

       Indian scientists can detect large undersea earthquakes in the Indian Ocean in real-time and provide a tsunami warning in 10-20 minutes after the earthquake occurs.

       Though the devastating tsunami of December 2004 has faded away from public memory, ITEWC continues its round the clock vigil for unusual happenings on the sea to give advance warnings to 25 countries apart from India.

       Intergovernmental Oceanographic Commission (IOC) of UNESCO (also known as UNESCO-IOC) accredited Indian Tsunami Early Warning Centre (ITEWC) as Tsunami Service Provider (TSP) for 28 Indian Ocean Rim (IOR) countries, along with Indonesia and Australia in 2011, for issuing regional warnings.

Go Back to the basics:

About INCOIS:

       INCOIS was established in 1999 as an autonomous body under the Ministry of Earth Sciences.

       INCOIS through Indian Tsunami Early Warning Centre (ITEWC) is the nodal agency to provide tsunami advisories to India.

       It is coordinating with the Disaster Management Officials (DMOs) for implementation of Tsunami Ready programme in India.

       It conducts IOWave Tsunami mock exercises biannually to strengthen the readiness to handle the emergency situations with stakeholders. 

Volcano:

       It is a rupture in the crust of a planetary-mass object (like Earth), that causes hot lava, volcanic ash, and gases to escape from a magma chamber below the surface.

       On Earth, volcanoes are generally found where tectonic plates (like Eurasian, Pacific, Somali, etc) diverge or converge. Examples- volcanoes occurring in mid-oceanic ridge and Ring of Fire.

       Eruption of volcanoes can be hazardous for humans and other lives living in its vicinity and volcanic ash may be a threat to aircrafts. Volcanoes can also cause

       Large volcanic eruptions inject water vapor (H2O), Carbon Dioxide (CO2), Sulphur Dioxide (SO2), ash, etc into the stratosphere to heights of 16-32 km.

Types of volcanoes based on frequency of eruption:

1. Active Volcano:

       Active volcanoes are volcanoes that are either erupting or on the verge of eruption.

       There are around 500 active volcanoes on Earth, excluding those submerged beneath the oceans.

       Every year, approximately 50 to 70 active volcanoes erupt, most of them being around the pacific “ring of fire”.

       Mount Etna (Italy), Hawaiian Islands (Pacific Ocean), Mauna Loa (Pacific Ocean), Mount Vesuvius (Italy), and Barren Island (India) are some examples of Active Volcanoes around the world. 

2. Dormant Volcano:

       A dormant volcano is one that is not erupting at the present but has erupted in the past and is expected to erupt again.

       The distinction between active and dormant volcanoes can be hazy.

       Some volcanoes can last thousands of years without erupting, thus they are theoretically predicted to erupt in the future, but it could take many lives.

       Another of the Big Island's five volcanoes, Mauna Kea, last erupted 3,500 years ago, but it is predicted to erupt again, but no date has been set.

       People living in the neighborhood of dormant volcanoes are frequently complacent and unprepared when an eruption occurs.

       This was the case in 1980 with Mt. St. Helens. 

3. Extinct Volcano:

       Extinct volcanoes are considered to be dormant and unlikely to erupt again.

       Example: Kohala, the Big Island of Hawaii's oldest volcano, hasn't erupted in 60,000 years and isn't expected to erupt again.

       However, because many Hawaiian volcanoes are in the process of rejuvenation, this classification isn't completely accurate.

       Aconcagua of the Andes is a typical example of an extinct volcano.