Japan’s tragic experience of witnessing catastrophic tsunami waves led to the creation of World Tsunami Awareness Day. The day, which is observed on November 5, serves as a reminder to educate people about lethal waves and what to do if they find themselves in one.
Tsunamis, despite their rarity, have been responsible for numerous fatalities, particularly during the 2004 Indian Ocean Tsunami.
WHAT IS A TSUNAMI?
The Japanese terms “tsu” (which means harbour) and “nami” are the roots of the word tsunami (which means wave). A tsunami is a series of extremely large waves produced by underwater motions that are often linked to earthquakes that occur beneath or around the sea.
A tsunami wave can also be produced by volcanic emissions, underwater avalanches, and rock falls on the coastline. They begin by developing the ocean floor upward, which causes the water mass to move. With waves arriving every five to one hour, tsunamis can attack the coastline and be dangerous for a considerable amount of time. They typically resemble dividers of water.
It’s possible that the secondary, third, fourth, or even much later waves are bigger than the original wave. Once a wave has submerged or flooded an area inland, it frequently retreats back toward the ocean, exposing the ocean floor. At that point, the next wave quickly surges onshore and carries debris that was previously transported by earlier waves.
WHAT ARE THE REASONS FOR TSUNAMI WAVES?
It may very easily be brought about by construction along zones of plate limit inadequacy. The majority of stable earthquakes take place in subduction zones, where a sea plate slides beneath a land plate or another younger sea plate.
For an earthquake to result in a tsunami wave, four essential conditions must be met:
:- The particles should either fall into the sea during the earthquake or occur underneath the water.
:- The tremor ought to be substantial, roughly measuring magnitude 6.5 on the Richter Scale.
:- The tremor should rupture the surface of the Earth and occur at shallow profundity, or less than 70 km below the Earth’s surface.
:- The seismic disturbance should cause the ocean floor to rise vertically (up to a few meters).
Extremely explosive volcanic eruptions have the potential to create deadly tsunami waves, despite the fact that they are not particularly common.
After the explosion and collapse of Indonesia’s Krakatoa (Krakatau) volcano’s abundance on August 26, 1883, one of the largest and most destructive waves ever recorded was created. This explosion killed 36,417 people, destroyed waterfront cities and towns along the Sunda Strait in both the islands of Java and Sumatra, and generated waves that reached a height of 135 feet.
Tsunamis caused by extraterrestrial impact (such as from space rocks or meteors) are a very rare occurrence. Although no meteor or space rock-related tsunamis have ever been documented in recorded history, scientists believe that if these celestial bodies were to impact the sea, a tremendous amount of water would undoubtedly be released to generate a wave.
A large amount of water can be driven into the ocean by a landslide that occurs near the coast, disturbing the sea and causing a wave. When the debris released by a submerged landslide flows violently, forcing the water ahead of it, it can also cause waves.
WORLD TSUNAMI AWARENESS DAY HISTORY
In accordance with resolution A/RES/70/203 passed on December 22, 2015, World Tsunami Awareness Day was observed on November 5 during the 70th United Nations General Assembly. This was done following the Indian Ocean Tsunami of 2004.
Following the adoption of the Sendai Framework for Disaster Risk Reduction at the third UN World Conference on Disaster Risk Reduction, this was proposed by 142 nations (WCDRR). The Japanese government planned this in March 2015 through the Ministry of Foreign Affairs in November 2015.
Do you Know?
:- An estimated 50% of the world’s population would reside in coastal regions by the year 2030.
:- In roughly 14 countries, the 2004 Indian Ocean tsunami claimed 227,000 lives.
:- In the previous ten decades, 58 tsunamis have been recorded.
:- Each tsunami claimed about 4600 lives.
:- Over the previous 20 years, tsunamis have contributed to about 10% of the world’s economic losses.
:- Islands and low-lying coastal areas are home to 700 million people.