A busy week for volcanoes: and Krakatau is waking up

First Katla was having a quake swarm, then Merapi erupted, now Krakatau is showing signs of increased activity. From John Seach at VolcanoLive:

"Saturday 30th October 2010
Krakatau Volcano, Indonesia

Activity has increased at Krakatau volcano, Indonesia. Over the past 4 days there has been an increase in explosions at the volcano. Yesterday there were 136 eruptions at the volcano, compared to a recent average of 10 per day. Krakatau volcano has been raised to level 2 alert. Krakatau became famous after the paroxysmal eruption on August 27, 1883. The volcano erupted more than 18 cubic km of ash to a height of 80 km, and produced a tsunami as high as 30 m along the west coast of Banten and south coast of Lampung.  The tsunami hit 295 villages and killed over 36,000 people."

At Wikipedia, "The island exploded in 1883, killing approximately 40,000 people, although some estimates put the death toll much higher. The explosion is still considered to be the loudest sound ever heard in modern history, with reports of it being heard nearly 3,000 miles from its point of origin. The shock wave from the explosion was recorded on barographs around the globe." With a Volcanic Explosivity Index (VEI) of 6,[3] the eruption was equivalent to 200 megatons of TNT (840 PJ) — about 13,000 times the nuclear yield of the Little Boy bomb (13 to 16 kt) that devastated Hiroshima, Japan, during World War II and four times the yield of the Tsar Bomba (50 Mt), the largest nuclear device ever detonated. More about Krakatau here.

Indonesian fishermen fear the volcano. The following excerpt is Google-translated from Indonesian-

Krakatau erupts, fishermen not go to sea
"The eruption of Mount Anak Krakatau left hundreds of fishermen in the District Cinangka, Serang, Banten, do not dare go to sea for fear of being exposed to material vulaknik of the mountain. "I had three today do not dare go down to the sea, fearing that the material will be exposed to rock fall from Mount Anak Krakatau," said the fisherman village of Pasauruan, Cinangka, Sarbini, Friday (29/10)."

Meanwhile, Mt. Merapi erupted again last night in the wee hours. Again, this excerpt below is Google-translated from Indonesian:

"...eruption of Mount Merapi, which re-occurred on Saturday (30/10) at around 00:16 pm is greater than ever. Eruptions are accompanied by loud rumbling sound, lava, and ash rain came down to the settlement residents in Jalan Kaliurang Kilometer 19, Yogyakarta. These conditions make people panic."His voice boomed, like lightning," said Parti..."

The following from Indonesia Today was posted on Friday, a day before Krakatau's alert level was also raised, but it explains what a level 2 means:

"The Centre of Vulcanology and Mitigation of Geology Disaster, a sub-department of the Ministry of Energy and Mineral Resources, on Friday announced that the status of eight volcanoes has been raised to level II or “caution level”, indicating increasing activity of these volcanoes. The eight volcanoes are: (1) Mount Sinabung, in Karo, North Sumatera; (2) Mount Talang, Solok, West Sumatera; (3) Mount Anak Krakatau, Lampung (Child of Krakatau Volcano); (4) Mount Papandayan, Garut, West Java; (5) Mount Slamet, Tegal, Central Java; (6) Mount Dieng, Wonosobo, Central Java; (7) Mount Semeru, Lumajang, East Java; and Mount Bromo, Probolinggo, East Java, detik.com reported on Friday."

"Level I is “Normal” status, means that there is no magma pressured from beneath the mount. Action recommended is routine observation, survey and study. When a volcano status is raised to Level II status or “Caution”, there is increasing activity above normal level and that there has been seismic activity. Under this situation, actions need to be undertaken include public campaign over the impact on the society if the volcano erupts..."
The third level or Level III is an “Alert” (yellow) status. Under this period, a volcano shows indications to erupt, seismic activity intensifies and that seismic data shows that seismic activity of the mount will continue to eruption level that could cause disaster. The fourth level or Level IV is a “”Danger” or “Red” status. During this period, the volcano shows indication that will soon erupt."

This week has been a busy one for volcanoes:

Kliuchevskoi and Shiveluch erupt in a busy week for volcanoes
"So, maybe I spoke too soon when I mentioned in passing how quiet the fall has been in the world of volcanic eruptions. In less than a week since I said this, we've had one of the more dramatic and tragic eruptions in the last decade in Indonesia (more on Merapi's eruption later today) and, lost in the Merapi news, were two eruptions on Kamchatka Peninsula of Russia. ... The first eruption occurred on Sunday, when Kliuchevskoi produced an ash plume that reached over ~30,000 feet...Meanwhile, yesterday Shiveluch produced its own explosive eruption as well. This eruption produced a 32,000 foot ash plume..."

I updated my global volcanism chart. Source data is from Smithsonian's Global Volcanism Program.


  1. This was really helpful for my volcano report


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