A large explosive eruption occurred in the evening of 13 February 2014, starting at 21:15 local time, after just two hours of precursor shallow earthquakes.
The explosion ejected an estimated 80-160 million m3 of tephra and ranks as a VEI 4 (or subplinian) event. The eruption plume rose to up to 27 km altitude and produced an umbrella cloud at 19 km altitude that drifted over the Indian Ocean.
Heavy ash fall occurred around the volcano and in large areas of Java. Fortunately, only few fatalities were caused by the eruption.
The (sub-)plinian eruption of Mt Kelut volcano on 13 Feb 2014
Satellite image of Kelut's eruption
Update Sun 02 Mar 11:15
Late on February 13, 2014, Kelut (also called Kelud) exploded with a powerful eruption. Satellites first detected the eruption plume at 11:09 p.m. local time (16:09 UTC). At 12:30 a.m. (17:30 UTC), the Visible Infrared Imaging Radiometer Suite (VIIRS) on the Suomi NPP satellite acquired the top image as the mushroom-shaped ash plume reached above a lighter-colored cloud deck.
The eruption plume with beautiful gravity waves. NASA Earth Observatory image by Jesse Allen, using expediated data provided by the CALIPSO team. Caption by Holli Riebeek
Forty minutes later, at 1:10 a.m. (18:10 UTC), the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite flew over the plume with CALIOP, its lidar instrument. Acting like a laser range finder, CALIOP uses a laser to create a profile of clouds and particles in the atmosphere. The instrument recorded the ash cloud at nearly 20 kilometers (12 miles) altitude, with sections of the plume reaching to nearly 30 kilometers (19 miles).
from: Nasa Earth Observatory
Update Thu 20 Feb 11:25The website of the International Charter Space and Major Disasters has great annotated satellite images showing the volcano before and after the eruption as well as the extensive ash and lahar deposits. At the place of the 2007 lava dome, a crater of about 400 m diameter was formed by the explosion.
SO2 plume from the eruption not going to affect world's climate
Update Sun 16 Feb 11:30The SO2 aerosol plume from the eruption is drifting over the Indian Ocean. Despite the impressive explosion, in terms of quantity of SO2 ejected into the atmosphere, the eruption was a very modest event and is not going to affect earth's climate.
Credit: Simon Carn @simoncarn / Twitter https://twitter.com/simoncarn/status/434750482716708864/photo/1
Gravity waves in the eruption plume
The second picture shows the eruption column and umbrella cloud expanding at 19 km altitude, the top part of the column shooting over to 25-27 km altitude, and very nice gravity waves:
As the eruption column was propelled upwards, driven by positive buoyancy due to the enormous heat content, its momentum made it shoot over its buoyancy-equilibrium level at 19 km, reaching up to 27 km. Afterwards, the plume sank back again now due to its weight and began spreading laterally into the umbrella cloud. As the plume swung down and above its equilibrium level (where buoyancy is zero), it created the so-called gravity waves visible in the picture. They are comparable to those waves induced when a stone is thrown into a lake and produces ring-shaped surface waves.
Credit: imon Carn @simoncarn / Twitter: https://twitter.com/simoncarn/status/434730560947118080/photo/1 (CALIPSO lidar data for Kelud eruption show nice gravity waves in the umbrella cloud at ~19 km altitude)
Destruction caused by the eruption
Update Sun 16 Feb 11:17Our correspondents Aris and Andy sent us some impressions from the devastated areas near Kelut. The village Pandan Sari (Ngantang) is totally destroyed. Up to 1 meter of tephra (ash, lapilli and small bombs) have fallen in places and 30 cm of ash is found inside houses.
Andi sent the following impressions:
Kelut volcano (East Java, Indonesia): eruption update - 4 fatalities, new size estimates
Saturday Feb 15, 2014 13:42 PM | BY: T
Ash emissions from Kelut yesterday (photo taken from Blitar)
Traces of recorded infrasound waves pointing back to Kelut (CTBTO, facebook.com/CTBTO)
Additional details and new estimates about the recent explosion are emerging. Unfortunately, a 4th fatality caused by the eruption has now been confirmed by BNPB. All victims were within 7 km of the volcano. More than 100,000 people have been evacuated.
Ash emissions from Kelut yesterday (photo: @hilmi_dzi / Twitter)
Fast rise of magma?
One of the most remarkable aspects of the eruption was how quickly it built up, suggesting a very fast rise of magma occurred in the hours before the explosion. VSI mentioned that there were only 2 hours between the appearance of shallow earthquakes (the typical immediate precursors) and the onset of the eruption itself. With such little warning time, it was difficult to implement an effective evacuation, but still, one should recognize that Indonesian authorities have done a marvelous job. Still, it is a small wonder that there were not many more fatalities. Most of this is to be attributed to the fact, that the eruption seems not to have produced any or at least no larger pyroclastic flows (which in itself is also a small wonder).
New estimates of the size of the eruption
The latest estimates of the erupted tephra volume are in the range of 120-140 million m3, which puts the explosion into the subplinian category with a low 4 on the Volcanic Explosivity Index scale (VEI). The plume seems to have reached up to 20 km altitude, analysis of satellite data suggest. These values put the eruption to be the largest in recent years, since the 2010 eruption of Puyehue-Cordon Caulle in Chile.
The explosion produced also one of the largest-ever recorded volcano-related infrasound waves. The pressure waves were picked up by stations all over the world, the furthest one being IS53 in Fairbanks, Alaska at >11.000 km or >6.800 mls, and the calculated traces point all into the direction of Kelut.
Kelud volcano (East Java, Indonesia) activity update
Friday Feb 14, 2014 19:58 PM | BY: TOMPFEIFFER
Ash from the eruption is still drifting over the eastern Indian Ocean. More than 100,000 people have reportedly evacuated areas close to the volcano. Heavy ash fall occurred in vast areas of Java. A preliminary judgement of the erupted ash suggests that the explosion was a magmatic event, i.e. triggered by a new bash of fresh magma that seems to have risen very quickly to the surface:
The ash plume of Kelut over the Indian Ocean (NASA earth observatory)
Our correspondent Andi wrote: "Jogja and many cities in the west and east of Java is covered by raining ash and layered until 3-4 mm. It's terrible that the ash could reach Jogja and other cities until 500 km away from Kelud as well as covered Borobudur temple again as in eruption 2010. ... The color (of the ash, rmk) is white powder and some black particles inside as well that maybe there is some pyroxene (small black particles)."
Kelut volcano (East Java, Indonesia): eruption update - 3 fatalities confirmed, evacuations
Friday Feb 14, 2014 11:32 AM | BY: T
The eruption of Kelut last night (image: pic.twitter.com/ypy7kx9615 / @hilmi_dzi)
A large SO2 plume is drifting over the Indian ocean (NOAA)
BNPB (Civil protection) confirmed 3 fatalities (indirectly or directly) caused by the eruption: two as result of breathing difficulties caused by the ash, one as a road accident during evacuation. All of the victims were in Pandasari village less than 7 km from the volcano where 20 cm of ash has fallen.
The ash plume from Kelut's eruption over the Indian Ocean seen from NASA's Terra satellite this morning
So far, 76,388 people are confirmed evacuated into 293 shelters so far, while evacuation efforts within the 10 km exclusion zone continue.
Preliminary estimations are that the eruption produced 80 million cubic meters of tephra. At the moment, the volcano continues to emit ash and steam, accompanied by tremors. The government of East Java has declared the state of emergency for the affected area. 350,000 dust masks are being distributed.
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