Volcanic Eruption in Ethiopia

Context

Recently, a massive cloud of ash from the Hayli Gubbi volcano eruption in Ethiopia reached northwestern India due to strong winds. This ash cloud disrupted flights in Delhi-NCR, Rajasthan, Gujarat, Maharashtra, and Punjab for several hours.

About Hayli Gubbi Volcano

• Introduction: It is a dormant volcano located in Ethiopia.
• ​​Eruption: It erupted for the first time in approximately 10,000 years, spewing a large amount of volcanic ash into the atmosphere and reaching India across the Red Sea.
• Location: This volcano is located in the Horn of Africa, specifically in the Afar Region of Ethiopia. This location is part of the East African Rift System.
• Seismic Zone: The Afar Region of Ethiopia is part of the East African Rift Valley, a highly seismic and volcanic zone. Tectonic plates are moving apart here, causing frequent earthquakes and volcanic eruptions.

Composition of Volcanic Ash

• Volcanic ash is primarily composed of silica, fine glass particles, minerals (feldspar, quartz), sulfur dioxide, and other gases.
• This ash is fine-grained and can damage airplane engines, so it is considered a serious hazard to air travel.

Damage and Impacts

• Ashfall in areas near Ethiopia caused temporary health problems for the local population.
• Changes in air routes and worsening conditions led to the cancellation or diversion of several international flights.
• Aviation activities around the Red Sea have been affected.

Impact on India

• The ash cloud was no more than 10 km high, so surface-level air quality was not significantly affected. However, the ash cloud entered the Indian region via Central Asia.
• According to the India Meteorological Department (IMD), its impact in India was very limited and short-lived.
• This caused flights of various national and international airlines (IndiGo, Akasa Air, KLM) to be cancelled or delayed for several hours. Reduced visibility prompted increased caution in aviation operations.

Causes of Volcanic Eruptions

• Temperature increases as one moves deeper into the Earth's core. The geothermal gradient refers to the heat flowing from the Earth's hot interior to its surface, with the Earth's temperature increasing with depth.
• At a certain depth, this heat becomes so intense that it melts rocks. These molten rocks are called magma.
• Magma is lighter than solid rock, so it rises and collects in magma chambers. These chambers are found at shallow depths of six to ten kilometers below the Earth's surface.
• Magma collected in these chambers is ejected through vents and cracks toward the Earth's crust, which is called volcanic eruption. The magma that reaches the Earth's surface is called lava.

Eruption Intensity

• Volcanic eruptions vary in intensity and explosiveness depending on the composition of the magma. Runny magma is less explosive and often less dangerous.
• Gases in runny magma are able to escape, and lava flows steadily and relatively slowly from the volcano's mouth.
• Because lava flows slowly, surrounding areas have sufficient time to take protective measures.
• If magma is thick and viscous, it makes it difficult for gases to escape continuously. These gases build up pressure to reach the mouth and are released all at once. This causes the lava to explode into the air and break into fragments called tephra. These fragments can range in size from small particles to massive boulders, which are extremely dangerous.
• The Volcanic Explosivity Index (VEI) is a scale used to measure a volcano's explosivity. It ranges from 1 to 8.

Types of Volcanoes Based on Eruption

• Active Volcano: A volcano that has erupted within the Holocene (the last 11,650 years) is considered active.
• Dormant Volcano: An active volcano that is not currently erupting but has the potential to erupt in the future. Mauna Loa has been dormant for the past 38 years.
• Extinct Volcano: There is no possibility of any future volcanic activity. Britain's highest mountain, Ben Nevis, is a dead volcano.