Indonesia's Anak Krakatau volcano shrinks to quarter-size after eruption

Scientists say the Anak Krakatau volcanic island in Indonesia has lost three-quarters of its volume since it erupted a week ago, causing a deadly tsunami. And it is also considerably shorter.

Indonesia's Anak Krakatau volcano, whose eruption and collapse last week caused a tsunami that claimed the lives of more than 420 people, is now only about a quarter of the size it was before its outburst, scientists say.

The height of the volcano was just 110 meters (360 feet) on Friday, compared with 338 meters in September, the Center for Volcanology and Geological Disaster Mitigation said. The island has also lost three-quarters of its volume, according to the center, having shed between 150 and 180 million cubic meters (5.2 billion-6.3 billion cubic feet) of material since the eruption on December 22.

Japan's space agency has released before-and-after satellite images showing that a 2 square kilometer (0.77 square mile) piece of the volcanic island has collapsed into the sea.

The Japanese satellite images show the changes in the volcano

The scale of the island's collapse corresponds to the power of the tsunami it unleashed on more than 300 kilometers (186 miles) of coastline in Sumatra and Java, where waves of 2 meters or higher were experienced.

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The tsunami caused considerable destruction and displaced more than 40,000 people

Dangerous offspring

Anak Krakatau, which means "Child of Krakatoa," emerged around 1928 in the crater left by its forerunner, the infamous Krakatoa volcano. Krakatoa had erupted in 1883, killing at least 36,000 people and setting off a period of global cooling owing to the ash it propelled into the atmosphere.

Anak Krakatau had already erupted dramatically in July 2018

Despite the reduction in Anak Krakatau's mass, which experts say means that any tsunami it produced now would be less severe, authorities have warned residents to stay at least a kilometer away from the coastline of the Sunda Strait, the body of water separating Java and Sumatra.

Indonesia is one of the most disaster-prone regions on earth, as it sits on the so-called Pacific Ring of Fire, a belt of frequent volcanic activity caused by the collision of tectonic plates.

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Volcano triggers tsunami in Indonesia

Searching for survivors

Indonesian rescue workers searched for victims among debris in Pandeglang after a tsunami hit the Sunda Strait. Pandeglang was one of the areas most affected and many of the injured needed orthopedic and neurosurgery procedures.

Volcano triggers tsunami in Indonesia

Erupting volcano

Authorities said the tsunami was triggered by the Anak Krakatau volcano. It had been spewing ash and lava for months before a 64 hectare section of it collapsed.

Volcano triggers tsunami in Indonesia

Caught off guard

Rudi Suhendar, the head of Indonesia's Geological Agency at the Ministry of Energy and Mineral Resources, told DW that the tsunami caught everyone off guard because of the absence of an earthquake. "We only have the early warning system when there is an earthquake before the tsunami," he said.

Volcano triggers tsunami in Indonesia

Many dead and injured

The death toll continued to rise in the days after the tsunami with hundreds dead and more than a thousand injured on the islands of Java and Sumatra, according to Indonesia's disaster mitigation agency.

Volcano triggers tsunami in Indonesia

Fear of another tsunami

The tsunami displaced thousands of people from their homes. Word of another tsunami caused many people to flee and seek refuge. Some climbed to the top of mosques, such as this one in Sumur village, to take shelter.

tj/ng (AFP, AP)

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