Tsunami ( Natural Disaster )
A tsunami is a huge volume of moving seawater. These giant waves can travel for thousands of miles across the sea and still have enough energy and force to destroy buildings, trees, wildlife and people.
It can be triggered by an undersea earthquake, landslide or volcanic eruption. In deep water tsunami waves can extend thousands of feet into the sea, and reach speeds of 500mph, almost fast enough to keep up with a jet airplane. There can be up to a hundred miles between each wave, which may be just a few feet above the sea.
Most Tsunamis are caused by undersea earthquakes. These underwater earthquakes cause disruption to the seafloor and, in turn, the overlying water. A tsunami and has nothing to do with tides although it is sometimes mistakenly called a tidal wave.
Sometimes when an ocean island collapses it causes a huge displacement of water which can also create a tsunami. Very rarely, a tsunami can be created by a giant meteor hitting the sea!
Scientists found traces of a huge meteor rock that collided with the Earth 3.5 billion years ago and landed in the sea, which may have created a giant tsunami that drastically changed coastlines and wiped out almost all life on land.
The Pacific Ocean experiences more tsunamis than anywhere else in the world. Tsunamis have also occurred in the Caribbean and Mediterranean Seas, and the Indian and Atlantic Oceans.
The December 2004 Asian tsunami is the deadliest in recorded history with a death toll of nearly 300,000. It was triggered by the fourth most powerful earthquake since 1900, estimated to measure 9.15 on the Richter scale.
Many people were killed by the Asian tsunami because they went down to the beach to see the exposed seafloor caused by the retreating of the sea. If you see the sea receding unusually quickly or far it’s a good sign that a big wave is on its way.
Before 2004 the most damaging tsunami on record was in 1782, following an earthquake in the South China Sea, which killed an estimated 40,000 people.
The Indian Ocean tsunami travelled as much as 3,000 miles to Africa and still had enough force to cause enormous destruction. For example, Somalia was hit harder than Bangladesh despite being much further away.
An earthquake off the coast of Chile in 1960 produced a tsunami that had enough force to kill 150 people in Japan after a journey of 22 hours and 10,000 miles.
In 1775, the Lisbon earthquake created a tsunami in the North Atlantic that killed as many as 60,000 people in Portugal, Spain and North Africa. This quake caused a tsunami as high as 23 feet in the Caribbean.
Another of the most deadly tsunamis in recorded history followed the eruption of the volcano Krakatoa in 1883, which destroyed the volcano completely and killed more than 36,500 people across the South Java Sea.
tsunami in Banda Aceh