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Today’s faulty tsunami warning is a reminder that tsunamis can happen on the US East Coast, too

A similarly massive quake is less likely in the Atlantic Ocean, Popham says. But that doesn’t mean the risk of a tsunami is zero. Underwater avalanches and volcanoes can also move enough water to generate the powerful waves of a tsunami.

To understand why, it helps to imagine the Earth’s crust fitting together like a jigsaw puzzle, and each of the pieces is called a tectonic plate. When plates sliding past each other get stuck, they can build up stress until they finally rupture — causing an earthquake. The earthquakes especially prone to producing tsunamis are the ones that occur where an oceanic plate scoots underneath a continental plate, called a subduction zone.

Unlike the Pacific Ocean, there aren’t any major subduction zones in the Atlantic except the ones underneath the Caribbean Sea. So there are fewer quakes that could generate dangerous tsunamis that would threaten the East Coast. And in the Gulf Coast, none of the tsunamis in recorded history were more than 3.3 feet (1 meter) tall.

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Indonesian city hit by tsunami after powerful quake

A powerful earthquake hit central Indonesia on Friday, causing a tsunami that slammed into a city on Sulawesi island with officials saying the tremor had levelled “many” buildings.

The shallow 7.5 magnitude quake sparked terror among locals who fled into the streets and raced to higher ground fearing tsunami waves.

The disaster agency briefly issued a tsunami warning before lifting it.

But dramatic video footage filmed from the top floor of a parking ramp spiral in Palu, a city of 350,000 nearly 80km (50 miles) from the quake’s epicentre, showed a churning wall of whitewater mow down several buildings and inundate a large mosque.

The tsunami reached a maximum height of 1.5m (five feet), the disaster agency later said.

People living hundreds of kilometres from the epicentre reported feeling the massive shake, hours after a smaller jolt killed at least one person in the same part of the Southeast Asian archipelago.

There were no immediate reports of deaths or injuries after the latest tremor, but it was a higher magnitude than a series of quakes that killed hundreds on the island of Lombok this summer.

The quake hit just off central Sulawesi at a shallow depth of some 10km just before 6pm local time (1100 GMT), the US Geological Survey said.

“There are reports that many buildings collapsed in the earthquake,” National Disaster Agency spokesman Sutopo Purwo Nugroho said in a statement.

“Residents panicked and scattered out of their homes.”

Pictures supplied by the agency showed a badly damaged shopping mall in Palu where at least one floor had collapsed onto the storey below.

Other pictures showed major damage to buildings, with rubble strewn about the road and large cracks running through pavements.

Facebook Live video showed long traffic jams formed in some parts of the region as terrified residents packed into cars, trucks and motorbikes to flee to higher ground following the tsunami warning.

Search and rescue teams have been dispatched to hard-hit areas, Nugroho said.

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Tsunami and Bangladesh

Tsunami is a series of very long waves generated by any rapid, large scale disturbance of the sea or by sea floor displacements from large undersea earthquakes. Thus tsunami is defined as a large destructive ocean wave caused by an underwater earthquake or some other movement of the earth’s surface or some geologic processes like undersea landslide or volcanic eruption.
Tsunamis can cause great destruction and loss of life within a minute on shores near their source. They are capable of obliterating coastal settlements, and may cause severe coastal flooding and ecological disruption of coastal areas. It is very hard to escape violent disasters caused by tsunami.
But it is very important to create public awareness, improved tsunami detection, mitigation and warning system for avoiding huge loss of life and property. Experts have suggested the following steps: i. Preservation of coral reef and natural mangrove forests; ii. Afforestation in coastal areas; iii. To keep a pollution free sea; iv. Stop excessive fishing and introduce modern sustainable fish catching methods; v. Public dwellings should be kept at least 500 meters away from a seashore, coastal embankment etc.