Indonesia tsunami: Death toll climbs to 373, says national disaster agency
TSUNAMI BREAKS THROUGH WALL BEHIND THE BAND, 'SEVENTEEN'.
Only one of the band members survive.
"Underwater I could only pray 'Jesus Christ help!'," Zack, a crew member of the rock band Seventeen, said in an Instagram post describing how he struggled in the water.
"In the final seconds I almost ran out of breath," he said, adding he survived by clinging to part of the collapsed stage.
At a news conference, PLN said 29 employees and relatives had died and 13 were missing.
December 23, 2018
https://www.thesun.co.uk/news/8047859/krakatoa-eruption-death-toll-latest-indonesia-tsunami/
Large part of Anak Krakatau has collapsed into the sea - reconstruction of the eruption
The combined information allows a rough reconstruction of the events:
#1 A new surge of magma arrives in the upper conduit of Anak Krakatau from around 20-21 Dec, causing increasing explosive and effusive activity - strombolian explosions or lava fountains, and lava flow emission - from the summit vent. It looked more or less like this:
(video from a similar paroxysm in Sep 2018)
A photo submitted by a visitor, taken on 22 Dec at 11:15 shows the advancing lava front close to the southern shore and strong strombolian explosions, which occurred at intervals of 15-30 seconds according to the report. This activity probably reached its peak on the evening of 22 Dec, when it was clearly visible by naked eye from more than 40 km away on the coast.
#2 In the evening of 22 Dec, lava fountains fed flows that reached the sea, probably on the south or southeast shores of Anak Krakatau, in similar locations as during previous episodes this year.
#3 Around 21:00 local time, the weight of rapidly accumulated lava on the subaerial and submerged cone of Anak Krakatau triggered an instability and a larger landslide removed a part of the southwestern cone - a flank collapse occurred. This rapid displacement caused the (small, but devastating) tsunami which reached the Java coast around 21:30 (local time).
#4 As a consequence, sea water gained access to large masses of hot rocks and possibly the conduit itself, triggering an ongoing series of steam explosions that produced the steam and ash plume first observed later this morning on satellite data and seen in this video:
Erosion of material from the ongoing explosive activity and along the new shoreline continues to eat away parts of the island.
What will come next?
This is difficult to say, but at least to a large extent it will depend on how much magma continues to rise, whether new collapses occur and so on. A possibility of even larger explosions, pyroclastic flows, tsunamis is clearly increased.
The alert level of the volcano was raised to red.
#1 A new surge of magma arrives in the upper conduit of Anak Krakatau from around 20-21 Dec, causing increasing explosive and effusive activity - strombolian explosions or lava fountains, and lava flow emission - from the summit vent. It looked more or less like this:
(video from a similar paroxysm in Sep 2018)
A photo submitted by a visitor, taken on 22 Dec at 11:15 shows the advancing lava front close to the southern shore and strong strombolian explosions, which occurred at intervals of 15-30 seconds according to the report. This activity probably reached its peak on the evening of 22 Dec, when it was clearly visible by naked eye from more than 40 km away on the coast.
#2 In the evening of 22 Dec, lava fountains fed flows that reached the sea, probably on the south or southeast shores of Anak Krakatau, in similar locations as during previous episodes this year.
#3 Around 21:00 local time, the weight of rapidly accumulated lava on the subaerial and submerged cone of Anak Krakatau triggered an instability and a larger landslide removed a part of the southwestern cone - a flank collapse occurred. This rapid displacement caused the (small, but devastating) tsunami which reached the Java coast around 21:30 (local time).
#4 As a consequence, sea water gained access to large masses of hot rocks and possibly the conduit itself, triggering an ongoing series of steam explosions that produced the steam and ash plume first observed later this morning on satellite data and seen in this video:
Erosion of material from the ongoing explosive activity and along the new shoreline continues to eat away parts of the island.
What will come next?
This is difficult to say, but at least to a large extent it will depend on how much magma continues to rise, whether new collapses occur and so on. A possibility of even larger explosions, pyroclastic flows, tsunamis is clearly increased.
The alert level of the volcano was raised to red.
At least 222 people dead
Update Sun 23 Dec 2018 11:05
As evening breaks on the west coast, BNPB updated the death toll to at least 222 victims, 843 injured and 28 missing people. Damage along the coast is extensive.
Update Sun 23 Dec 2018 17:18
Steam and ash explosions at Krakatau seen this morning (Image: Dicky Adam Sidiq/kumparan)
Satellite image taken yesterday after the collapse, possibly showing one of the tsunami waves (image: Sentinel 1, annotations by R. Natsuaki @flyingwktk / twitter)
An overflight of was undertaken today by the Kumparan agency and revealed continuous, violent phreatomagmatic explosions, i.e. driven by lava and water interaction.
Comparison of Anak Krakatau before and after the flank collapse (image: Sentinel 1)
Example of a (small) lateral blast from Krakatoa:
Update Mon 24 Dec 2018 15:46
Something like this might have occurred on Saturday, leading to the partial collapse of the cone.
What caused the tsunami?
Update Mon 24 Dec 2018 14:58
- a slide simply caused by the weight of rapidly accumulated new lava material on the flanks, both above and below water
- a sudden lateral blast caused by an explosion as magma rising could not be released quickly enough from the established summit vent.
It is also unclear how much of the island disappeared by the initial event and how much crumbled away during the following erosion by eruption and adjustments by gravity.
A sketch published on twitter illustrated the version implying a larger lateral blast:
Call for donations for victims
Update Mon 24 Dec 2018 10:50
Tsunami damage on Java's west coast (image: Øystein Lund Andersen / facebook)
You can do this through PayPal:
History:
An 1888 lithograph of the 1883 eruption of Krakatoa.
Credit: Public domain
The eruption of Krakatoa, or Krakatau, in August 1883 was one of the most deadly volcanic eruptions of modern history. It is estimated that more than 36,000 people died. Many died as a result of thermal injury from the blasts and many more were victims of the tsunamis that followed the collapse of the volcano into the caldera below sea level. The eruption also affected the climate and caused temperatures to drop all over the world.
Blogger Dee note: Maybe Al Gore can now shut up about Global Warming if we have a replay of 1883. Oh, that's right, they now call it "Climate Change".
New eruptive phase begins at Anak Krakatau, Indonesia
Posted by TW on in categories Featured articles, Volcanoes
Since February 17, 2017, a strong thermal signal is visible on satellite data from what seems to be the summit of Anak Krakatau (Child of Krakatau), the site of frequent eruptions since 1927. The last eruption of this volcano occurred on March 31, 2014 (VEI 1).
What causes the thermal signal exactly is unknown. While non-volcanic causes (e.g. forest fires) cannot be ruled out, it is more likely that a new mass of lava has arrived at the crater, probably in the form of a new dome, Volcano Discovery explains.
"In that case, Krakatau might be entering a new eruptive phase, something which would not be a surprise, statistically. So far, there is no confirmation of significant ash emissions observed, which could mean that the activity, if there is, is only effusive for now."
The last significant eruptive phase of this volcano began on July 31, 2011 and ended on September 9, 2012. It had Volcanic Explosivity Index of 2 (of 8).
History from the History Channel:
The volcanic island of Krakatoa near Indonesia erupted August 27, 1883, killing thousands in one of the worst geologic disasters of modern times.
The beginning of the amazing events at Krakatoa in 1883 date to May 20 when there were initial rumblings and venting from the volcano, which had been dormant for about 200 years. Over the next three months, there were regular small blasts from Krakatoa out of three vents. On August 11, ash started spewing from the small mountain. Eruptions got progressively stronger until August 26, when the catastrophe began.
At noon, the volcano sent an ash cloud 20 miles into the air and tremors triggered several tsunamis. This turned out to be just a small indication, however, of what would follow the next day. For four-and-a-half hours beginning at 5:30 a.m. on August 27, there were four major and incredibly powerful eruptions. The last of these made the loudest sound ever recorded on the planet. It could be heard as far away as central Australia and the island of Rodrigues, 3,000 miles from Krakatoa. The air waves created by the eruption were detected at points all over the earth.
The eruption had devastating effects on the islands near Krakatoa. It set off tremendous tsunamis that overwhelmed hundreds of villages on the coasts of Java and Sumatra. Water pushed inland several miles in certain places, with coral blocks weighing 600 tons ending up on shore. At least 35,000 people died, though exact numbers were impossible to determine. The tsunamis traveled nearly around the world–unusually high waves were noticed thousands of miles away the next day.
The volcano threw so much rock, ash and pumice into the atmosphere that, in the immediate area, the sun was virtually blocked out for a couple of days. Within a couple of weeks, the sun appeared in strange colors to people all over the world because of all the fine dust in the stratosphere. Over the ensuing three months, the debris high in the sky produced vivid red sunsets. In one case, fire engines in Poughkeepsie, New York, were dispatched when people watching a sunset were sure that they were seeing a fire in the distance. Further, there is speculation that Edvard Munch’s 1893 painting “The Scream” depicting a psychedelic sunset may have actually been a faithful rendering of what Munch saw in Norway in the years following the eruption of Krakatoa. The amount of dust in the atmosphere also filtered enough sun and heat that global temperatures fell significantly for a couple of years.
Krakatoa was left only a tiny fraction of its former self. However, in the intervening years, a small island, Anak Krakatoa (“Son of Krakatoa”) has arisen from the sea. It is growing at an average of five inches every week. This island is receiving a great deal of scientific attention, as it represents a chance to see how island ecosystems are established from scratch.
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