The deadly tsunami that swamped India’s southern coast two decades ago was a one-off disaster, but storms that are growing ever more intense spark panic each time howling gales whip up waves.

Maragathavel Lakshmi shudders when she hears lashing rains or winds, recalling how her daughter was swept away when the 2004 tsunami, triggered by a huge earthquake off Indonesia, crashed onshore almost without warning.

“Weather alerts have made life easier, but the fear of what a heavy rain or strong wind might bring is still there,” 45-year-old Lakshmi said.

More than 220,000 people were killed as the devastating waves hit shorelines around the Indian Ocean, including 16,389 in India, according to the international disaster database EM-DAT.

Fear of the weather is based on a very real threat — and the risks are increasing.

Dangerous cyclones, the equivalent of hurricanes in the North Atlantic or typhoons in the northwestern Pacific, are an annual menace.

Better forecasting and more effective evacuation planning have dramatically reduced death tolls, but scientists say human-driven climate change is intensifying their power.

“Summers are very harsh now and rains are heavier,” Lakshmi said, saying weather alerts sent her anxiety soaring.

A warmer atmosphere holds more water, meaning rains are heavier.

“Strong winds scare us,” said her husband Maragathavel, who like many in the region goes by only one name.

Also Read | Remembering the Indian Ocean Tsunami

“Every time it rains heavily, water (floods) our area,” the 49-year-old fisherman added. “It seems on those days that the sea has still not left us.”

‘Very afraid’

The December 26, 2004 disaster was not caused by climate change but by a 9.1 magnitude earthquake that struck off Indonesia’s Sumatra.

Hours later, Lakshmi heard a loud rumble and then saw enormous waves — rising as high as 40 metres (130 feet) — approaching her neighbourhood on the shore in Akkaraipettai, their village in Tamil Nadu state.

Lakshmi showed a photograph of her daughter Yashoda, who her father had been looking after for the day next door when the waves struck.

“She would have been 22 years old now,” Lakshmi said tearfully.

The 45-year-old remembers people getting swept away or holding on to whatever they could.

“Some people were naked or barely had any clothes left on them,” she said.

The tsunami also hit the chain of Andaman and Nicobar islands, where at least 4,000 people were killed. The victims included 109 Indian air force pilots, crew and around 40 of their relatives.

At least 870,000 people were left homeless in India.

Many, like Lakshmi, were moved to new settlements inland.

Their neighbour, fisherman P. Mohan, 46, said weather alerts still gave him shivers of fear.

“If I see some warning about the weather, I do not even step out of the house,” he said.

“Until the rains or cyclone — whatever is the warning — comes and goes away, I am very afraid.”

‘Cannot control nature’

Mohan had a rod put into his leg after being injured in the tsunami, which also killed his mother.

Neighbours had last seen her sitting beside the sea when the waves hit.

He could not identify her from the “swollen and disfigured” corpses laid out for identification in the days after the tsunami.

“Was she buried along with other people who could not be identified? Is her body still in the sea?” he asked. “I do not know.”

A few friends told him that they might have seen his mother’s body amid other unidentified corpses.

It took him a decade to fully accept her loss and hold symbolic final rites.

A seawall made of concrete and bricks of homes destroyed by the tsunami now divides land from water.

Villagers hold prayers each day at a temple to a Hindu deity believed to protect them from the sea.

But Mohan said he now simply accepted his fate.

“God cannot control nature,” he said. “What has to come, will come.”

A house is seen collapsed in Oosaki town, Kagoshima prefecture, southern Japan Friday, August 9, 2024, following Thursday’s powerful earthquake.
| Photo Credit: AP

Japan’s earthquake scientists say the country should prepare for a possible “megaquake” one day that could kill hundreds of thousands of people – although they stress the warning does not mean a colossal tremor is imminent.

The Japan Meteorological Association (JMA) warning is the first issued under new rules drawn up after a 2011 earthquake, tsunami and nuclear disaster killed around 18,500 people.

What does the warning say?

The JMA’s “megaquake advisory” warns that “if a major earthquake were to occur in the future, strong shaking and large tsunamis would be generated. The likelihood of a new major earthquake is higher than normal, but this is not an indication that a major earthquake will definitely occur during a specific period of time,” it added.

The advisory concerns the Nankai Trough “subduction zone” between two tectonic plates in the Pacific Ocean, where massive earthquakes have hit in the past.

What is the Nankai Trough?

The 800 km undersea trough runs from Shizuoka, west of Tokyo, to the southern tip of Kyushu Island. It has been the site of destructive quakes of magnitude eight or nine every century or two. These so-called “megathrust quakes”, which often occur in pairs, have been known to unleash dangerous tsunamis along Japan’s southern coast.

In 1707, all segments of the Nankai Trough ruptured at once, unleashing an earthquake that remains the nation’s second-most powerful on record. That quake – which also triggered the last eruption of Mount Fuji – was followed by two powerful Nankai megathrusts in 1854, and then a pair in 1944 and 1946.

How much is at stake?

Japan’s government has previously said the next magnitude 8-9 megaquake along the Nankai Trough has a roughly 70% probability of striking within the next 30 years. In the worst-case scenario 300,000 lives could be lost, experts estimate, with some engineers saying the damage could reach $13 trillion with infrastructure wiped out.

“The history of great earthquakes at Nankai is convincingly scary,” geologists Kyle Bradley and Judith A. Hubbard wrote in their Earthquake Insights newsletter. And “while earthquake prediction is impossible, the occurrence of one earthquake usually does raise the likelihood of another”, they explained.

“A future great Nankai earthquake is surely the most long-anticipated earthquake in history – it is the original definition of the ‘Big One’.”

How worried should people be?

Japan is reminding people living in quake zones to take general precautions, from securing furniture to knowing the location of their nearest evacuation shelter. Many households in the country also keep a disaster kit handy with bottled water, long-life food, a torch, radio and other practical items.

But there’s no need to panic – there is only a “small probability” that Thursday’s (August 8, 2024) magnitude 7.1 earthquake is a foreshock, according to Bradley and Hubbard.

“One of the challenges is that even when the risk of a second earthquake is elevated, it is still always low. For instance, in California, the rule of thumb is that any given earthquake has around 5% chance of being a foreshock,“ they said.

A house is seen collapsed in Oosaki town, Kagoshima prefecture, southern Japan Friday, August 9, 2024, following Thursday’s powerful earthquake.
| Photo Credit: AP

Japan’s earthquake scientists say the country should prepare for a possible “megaquake” one day that could kill hundreds of thousands of people – although they stress the warning does not mean a colossal tremor is imminent.

The Japan Meteorological Association (JMA) warning is the first issued under new rules drawn up after a 2011 earthquake, tsunami and nuclear disaster killed around 18,500 people.

What does the warning say?

The JMA’s “megaquake advisory” warns that “if a major earthquake were to occur in the future, strong shaking and large tsunamis would be generated. The likelihood of a new major earthquake is higher than normal, but this is not an indication that a major earthquake will definitely occur during a specific period of time,” it added.

The advisory concerns the Nankai Trough “subduction zone” between two tectonic plates in the Pacific Ocean, where massive earthquakes have hit in the past.

What is the Nankai Trough?

The 800 km undersea trough runs from Shizuoka, west of Tokyo, to the southern tip of Kyushu Island. It has been the site of destructive quakes of magnitude eight or nine every century or two. These so-called “megathrust quakes”, which often occur in pairs, have been known to unleash dangerous tsunamis along Japan’s southern coast.

In 1707, all segments of the Nankai Trough ruptured at once, unleashing an earthquake that remains the nation’s second-most powerful on record. That quake – which also triggered the last eruption of Mount Fuji – was followed by two powerful Nankai megathrusts in 1854, and then a pair in 1944 and 1946.

How much is at stake?

Japan’s government has previously said the next magnitude 8-9 megaquake along the Nankai Trough has a roughly 70% probability of striking within the next 30 years. In the worst-case scenario 300,000 lives could be lost, experts estimate, with some engineers saying the damage could reach $13 trillion with infrastructure wiped out.

“The history of great earthquakes at Nankai is convincingly scary,” geologists Kyle Bradley and Judith A. Hubbard wrote in their Earthquake Insights newsletter. And “while earthquake prediction is impossible, the occurrence of one earthquake usually does raise the likelihood of another”, they explained.

“A future great Nankai earthquake is surely the most long-anticipated earthquake in history – it is the original definition of the ‘Big One’.”

How worried should people be?

Japan is reminding people living in quake zones to take general precautions, from securing furniture to knowing the location of their nearest evacuation shelter. Many households in the country also keep a disaster kit handy with bottled water, long-life food, a torch, radio and other practical items.

But there’s no need to panic – there is only a “small probability” that Thursday’s (August 8, 2024) magnitude 7.1 earthquake is a foreshock, according to Bradley and Hubbard.

“One of the challenges is that even when the risk of a second earthquake is elevated, it is still always low. For instance, in California, the rule of thumb is that any given earthquake has around 5% chance of being a foreshock,“ they said.

Representational image of a seismograph recording an earthquake.
| Photo Credit: via Reuters

A magnitude-6.0 earthquake struck off northeastern Japan’s Fukushima region on Thursday, the Japan Meteorological Agency said, but no tsunami warning was issued.

There were no immediate reports of damage or injuries after the earthquake, whose epicentre had a depth of 40 kilometres (25 miles) and which was also felt in Tokyo.

TEPCO, the operator of the Fukushima nuclear power plant, said “no abnormalities” had been detected at the stricken plant or others in the region.

Japan, one of the world’s most tectonically active countries, has strict building standards designed to ensure structures can withstand even the most powerful earthquakes.

The archipelago, home to around 125 million people, experiences around 1,500 jolts every year, the vast majority of which are mild.

The United States Geological Survey put the magnitude of Thursday’s quake at 6.1, with a depth of 40.1 kilometres.

It comes a day after at least nine people were killed and more than 1,000 injured by a powerful earthquake in Taiwan.

Wednesday’s magnitude-7.4 quake damaged dozens of buildings in Taiwan and prompted tsunami warnings as far as Japan and the Philippines.

Japan’s biggest earthquake on record was a massive magnitude-9.0 undersea jolt in March 2011 off Japan’s northeast coast, which triggered a tsunami that left around 18,500 people dead or missing.

The 2011 catastrophe also sent three reactors into meltdown at the Fukushima nuclear plant, causing Japan’s worst post-war disaster and the most serious nuclear accident since Chernobyl.

The total cost was estimated at 16.9 trillion yen ($112 billion), not including the hazardous decommissioning of the Fukushima facility, which is expected to take decades.