Context:
Strong earthquakes, including a preliminary 7.6 magnitude, struck Japan, prompting tsunami warnings from North and South Korea, and Russia. Tsunami waves impacted various coastal areas in Japan, leading to urgent evacuation warnings.
Relevance:
GS I: Geography
Dimensions of the Article:
- Tsunami Overview
- Tsunami Preparedness in India
- Why is Japan Prone to Earthquakes and Tsunamis?
Tsunami Overview:
- Tsunami is a series of massive ocean waves caused by seismic activities like earthquakes or volcanic eruptions beneath the ocean.
- Characterized by long wavelengths and high energy, tsunamis can traverse entire ocean basins, leading to extensive destruction upon reaching coastlines.
- These waves can reach considerable heights, moving swiftly over deep waters and slowing down in shallower areas.
Factors Behind Tsunami Creation:
- Underwater Earthquakes:
- Shifting tectonic plates generate seismic waves, propagating through water and creating tsunamis.
- Volcanic Eruptions:
- Volcanic activity, especially under the ocean, displaces water, triggering tsunamis, particularly during volcanic island collapses or explosive eruptions.
- Landslides:
- Underwater landslides, caused by various factors, displace water, generating significant tsunami waves.
- Meteorite Impact:
- Rare but possible; the impact of a large meteorite or asteroid in the ocean can create tsunami-like waves.
- Underwater Explosions:
- Human activities, such as underwater explosions, have the potential to generate tsunamis.
Devastation Caused:
- Tsunami waves, traveling at high speeds across the open ocean, unleash devastating force upon reaching coastal areas.
- Unique energy and wavelength characteristics differentiate them from regular ocean waves, causing widespread damage during inundation.
Tsunami Preparedness:
- Early warning systems and preparedness measures play a crucial role in minimizing the impact of tsunamis on coastal communities.
- Swift responses and effective communication are essential components of mitigating the destructive effects of tsunamis.
Tsunami Preparedness in India:
Indian Ocean Tsunami Warning System (IOTWS):
- India actively participates in the Indian Ocean Tsunami Warning System (IOTWS).
- The system includes seismic and sea-level sensors strategically placed to detect underwater earthquakes and monitor sea level changes.
- Information collected is utilized to issue timely warnings to coastal communities.
Tsunami Early Warning Centre (ITEWC):
- The Tsunami Early Warning Centre (ITEWC) is situated at the Indian National Centre for Ocean Information Services (INCOIS) in Hyderabad.
- ITEWC provides tsunami advisories to stakeholders.
Public Awareness and Education:
- INCOIS, in collaboration with the National Disaster Management Authority (NDMA), conducts mock drills and organizes workshops/trainings on tsunami awareness and preparedness.
Enhancing Community Preparedness:
- INCOIS coordinates the implementation of the UNESCO-IOC “Tsunami Ready” initiative to enhance community preparedness.
- Villages like Venkatraipur and Noliasahi in Odisha have been recognized as Tsunami-ready communities by UNESCO-IOC, making India the first country in the Indian Ocean region to achieve this distinction.
Software and Multimode Dissemination:
- INCOIS has the necessary software for monitoring earthquakes and multimode dissemination of early tsunami warnings.
- The Decision Support System software automatically generates and disseminates warnings, integrating with the NDMA Common Alert Protocol (CAP) system.
- INCOIS has developed the “SAMUDRA” mobile application for effective access to marine users for ocean data resources and advisories.
Why is Japan Prone to Earthquakes and Tsunamis?
Pacific Ring of Fire:
- Japan is located along the ‘Pacific Ring of Fire,’ the most active earthquake tectonic belt globally, forming an imaginary horseshoe-shaped zone around the Pacific Ocean.
- The Ring of Fire is renowned for frequent earthquakes and volcanic eruptions.
Tectonic Plates Interaction:
- Within the Ring of Fire, several tectonic plates, such as the Pacific Plate, Eurasian Plate, and Indo-Australian Plate, continuously interact.
- The constant collision and subduction of these plates result in earthquakes, volcanic activities, and the potential for tsunamis.
2011 Earthquake and Tsunami:
- In 2011, Japan experienced a catastrophic 9.0 magnitude earthquake followed by a devastating tsunami.
- The northeastern coastal communities were severely impacted, causing the loss of around 18,000 lives and displacing tens of thousands.
- The tsunami triggered a nuclear meltdown at the Fukushima power plant, marking one of the most severe nuclear accidents since the 1986 Chernobyl disaster in the Soviet Union.
-Source: Indian Express
