Indonesian tsunami volcano lost two-thirds of its height

Anak Krakatoa is now just 110 metres high after losing two thirds of its height following the eruption that triggered the deadly
Anak Krakatoa is now just 110 metres high after losing two thirds of its height following the eruption that triggered the deadly tsunami

The Indonesian volcano which caused a tsunami that killed more than 400 people last week lost more than two-thirds of its height following the eruption which triggered the killer waves.

A section of Anak Krakatoa's crater collapsed after an eruption and slid into the ocean, generating the tsunami last Saturday night.

A visual analysis by the Indonesian volcanology agency found the volcano has lost more than two-thirds of its height, an official said Saturday.

Anak Krakatoa which used to stand 338 metres (1,109 feet) high was now just 110 metres tall.

The agency estimated the volcano lost between 150 and 180 million cubic metres of material as massive amounts of rock and ash have been slowly sliding into the sea following a series of eruptions.

"Anak Krakatoa is now much shorter, usually you can see the peak from the observatory post, now you can't," Wawan Irawan, a senior official at the agency, told AFP.

Before and after satellite images taken by Japan's space agency showed that a two square kilometre chunk of the volcanic island had collapsed into the water.

The volcano, whose name means Child of Krakatoa, was a new island that emerged around 1928 in the crater left by Krakatoa, whose massive 1883 eruption killed at least 36,000 .

Satellite images from the Japan Aerospace Exploration Agency show the changes in Anak Krakatoa (C) before and after the eruption
Satellite images from the Japan Aerospace Exploration Agency show the changes in Anak Krakatoa (C) before and after the eruption

The crater's status has been raised to high alert, the second-highest warning on Indonesia four-point danger scale.

The exclusion zone has been extended from two to five kilometres (1.2 to three miles).

A week after the tsunami, thousands of Indonesian Muslims attended a mass prayer on Saturday to remember the victims and pray for the safety of their tsunami-prone hometown.

Residents of Pandeglang regency, which was hit the hardest by the disaster, gathered in the early morning, some in tears as they chanted their prayers.

"I prayed for the victims and I also pray for the safety of the people who live in the tsunami affected area," Dadan Suryana, a tsunami survivor, told AFP.

"My prayer is for the victims to get help and be granted patience and I also pray the government will immediately help us to rebuild, to provide clothes and food, or at least to give us moral support," fellow congregant Dian Rosdiana said.

The exclusion zone around Anak Krakatoa has been extended from two to five kilometres
The exclusion zone around Anak Krakatoa has been extended from two to five kilometres

Authorities said at least 426 people were killed and 23 missing in the disaster.

Some 7,202 people suffered injuries and nearly 1,300 homes were destroyed after the waves crashed into the coastlines of western Java island and south Sumatra.

More than 40,000 people have been evacuated for fear of another as Anak Krakatoa continues to rumble.

Indonesia, a vast Southeast Asian archipelago, is one of the most disaster-hit nations on Earth due to its position straddling the so-called Pacific Ring of Fire, where tectonic plates collide.


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Dec 29, 2018
no one says, "it did a Mt St. Helens"

Dec 29, 2018
@S: That's because it didn't ??

Dec 29, 2018
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Dec 29, 2018
When?

When ever it damn well feels like it....

Dec 29, 2018
IMHO, the remaining sea-cliffs are perilously unstable. However, they are likely to fail and fall into shallow water, atop the rubble of the big collapse, mitigating their tsunami potential. Other reports suggest the active vent is now in semi-submerged 'Surtsey' mode, may rebuild itself above the water line. If it succeeds, the cone must re-grow to a height and volume that could be dangerous..
Without local instrumentation, there's no easy way to figure how much magma is rising, or if there's a shallow reservoir where water ingress may produce a catalysmic explosion.
Be NOT There...

Dec 29, 2018
My question is - why do they want the government to "rebuild" so soon?

Dec 29, 2018
My question is - why do they want the government to "rebuild" so soon?
HOA lawyers?

LMFAO

Dec 29, 2018
Well, it wasn't AGCC anyway. So much for the denier nutjobs claiming "teh siensetis say everthang is teh global waruming!"

Dec 29, 2018
And anybody who thought "Son of Krakatoa" wasn't a big risk totally blew it. This area will be scary for the next ten thousand years.

Dec 30, 2018
Now watch them build more huts on the beach areas for the second time, only to be swamped again in 10 years.

Dec 30, 2018
Now watch them build more huts on the beach areas for the second time, only to be swamped again in 10 years.

Yes, they probably will. Maybe you meant to insult those people, maybe not. Only you know.

If you did, I invite you to explore the US history of rebuilding along coastlines after disasters, or along rivers . . . the town in Hawai'i where I live needed two lethal tsunami to decide that the areas destroyed maybe shouldn't be rebuilt. And they had a long time to think about it, too (from 1946 to 1960).

And I won't even explore the stupidity of building and rebuilding on the slopes of one of our active volcanos.

Any archaeologist will tell you that people almost always rebuild what nature has destroyed, and usually in the same place -- not because they're stupid, but because they had good reasons to put a settlement there.

Dec 30, 2018
Alaska is a good example of reoccurring disasters & people stubbornly sticking it out.

Why? It's home!

If you were a Humane person? You would encourage all those people living in imminent danger zones, from around the world, to migrate to your community.

Dec 30, 2018
I dunno, if my house slid down into liquified permafrost I might decide to move back to someplace more sane.

Dec 31, 2018
I "think" this would be a most excellent forum to point out that "people" are neither reasonable nor rational!

"Cue the woocultist commentators!"

Jan 01, 2019
I "think" this would be a most excellent forum to point out that "people" are neither reasonable nor rational!

"Cue the woocultist commentators!"

@rrwillsj -- I would argue that what we're talking about (moving back to a location where there was a disaster) can be thought of as both reasonable and/or rational.

People do make choices. People do play the odds (as they see them). Sometimes they're wrong and get hammered.

What I'm really saying is that the universe of choices -- decision making in the face of uncertainty -- is vast, and what may seem unreasonable to us is not necessarily unreasonable to those making the choice.

It's certainly culture-bound, meaning that generally speaking people in different cultures are going to reckon the odds, the risks, and the consequences differently.

That's all.

Jan 01, 2019
wail, you make a damn good argument. Though I would disagree that land-hunger is determined by "culture".
I would think that lebensraum is more a biological compulsion.

Jan 01, 2019
wail, you make a damn good argument. Though I would disagree that land-hunger is determined by "culture".
I would think that lebensraum is more a biological compulsion.

I didn't mean to seem like I was talking about land hunger. I'm thinking more along the lines of "let's go back where we were," although to offer a near-by example (meaning in my part of Hawai'i) people bought land and built on a known rift zone (that had last erupted in 1960) because land was cheap, building code enforcement lax.... And many of them paid a heavy price.

Particularly after earthquakes, in many parts of the world, you see rebuilding-in-place.

Jan 01, 2019
Yeah, my wife & I almost bought into one of those developments. But that is First Worlder's having choices. Even if they turn out to be bad choices.

"Land-hunger"? I'm thinking mainly of the rest pf the World. Where people very rarely get to choose where they want to live. & earn enough to support their families.

It doesn't take many generations to exhaust the soil & strip the land. Fresh volcano created land? Uninhabited or maybe abamdoned by the former claimants? Who had fled the last eruption.

I guess it's Human Nature that so many people cannot resist the opportunity. Even knowing the risks.
Same as with flood plains.

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