Archives / 2014 / February

Small volcanic eruptions and the global warming ‘pause’

Wellcome Library, London  Mount Vesuvius emitting a column of smoke after its eruption on 8 August 1779. Coloured etching by Pietro Fabris, 1779.

Wellcome Library, London
A small eruption of Mount Vesuvius on 8 August 1779, part of a sequence that culminated in a moderate eruption. Coloured etching by Pietro Fabris, 1779. Copyrighted work available under Creative Commons Attribution only licence CC BY 2.0

A new paper in Nature Geoscience by Santer and colleagues revisits the volcanic scenarios used in modern climate model simulations. The authors consider the effects of including a ‘more realistic’ model for the influence of small volcanic eruptions on the climate system over the past two decades. Of course, more realistic means more difficult.. and one of the long-standing and unresolved problems with small volcanic eruptions is that not only are they small, but their consequences are unpredictable. These complications arise, in part, from the fact that the part of the volcanic system that is responsible for the climate impact are the emitted gases (notably, sulphur dioxide or SO2), and not the volcanic ash. In real volcanoes, these two parameters don’t seem to be very well correlated – and it has been well known for some time that small but explosive eruptions of sulphur-rich magmas might well have a disproportionate effect on the climate system (see, for example, Rampino and Self, 1984; Miles et al., 2004). For this reason, models of volcano-climate impact that only use information on eruption size (as measured by the Volcanic Explosivity Index) will usually only be a poor approximation to reality. A better representation might instead be a volcanic sulphur dioxide climatology, building on the extensive work of the volcanic emissions satellite-remote sensing community since the first volcanic plume satellite measurements in 1979. The currently most up to date compilations of volcanic SO2 emissions since 1996 can be found in Carn et al., (2003) and McCormick et al., (2013).

Reading between the lines, it looks as though Santer and colleagues have come to a similar conclusion – finding that their model simulations get a little closer to observations of tropospheric temperature trends when they introduce a ‘realistic’ volcanic scenario to simulate the past 25 years of eruptions. What a pity that the volcanic dataset they relied on to line up particular eruptions with aerosol optical depth perturbations was patched together from secondary sources.  Clearly, as they suggest, more work is needed – but why not start by bringing the  climate modeling community and volcanologists together to find out what we each think that we know ?

Further reading.

Carn SA et al. 2003 Volcanic eruption detection by the Total Ozone Mapping Spectrometer (TOMS) instruments: a 22-year record of sulphur dioxide and ash emissions, In: Oppenheimer et al. (eds), Volcanic Degassing, Geological Society, London, Special Publications 213, 177-202.

McCormick BT et al. 2013 Volcano monitoring applications of the Ozone Monitoring Instrument, In: Pyle DM et al. (eds), Remote Sensing of Volcanoes and Volcanic ProcessesGeological Society, London, Special Publications 280, 1259-291.

Miles GM, Grainger RG and Highwood EJ 2004 The significance of volcanic eruption strength and frequency for climate Q. J. R. Met. Soc. 130 2361–76

Rampino MR and Self S 1984 Sulphur-rich volcanic eruptions and stratospheric aerosols, Nature 310, 677 – 679

Santer B et al, 2014, Volcanic contribution to decadal changes in tropospheric temperature Nature Geoscience (2014) doi:10.1038/ngeo2098

Related posts.

For more information on William Hamilton and Vesuvius, try this delightful blog post by Karen Meyer-Roux.

Update on the eruption of Gunung Kelud

Area – thickness plot for Kelut fall deposits.  1990 data from Bourdier et al., 1997 (not all proximal data are plotted).

Preliminary ash thickness – isopach area plot for the February 2014 Kelut eruption. 1990 data from Bourdier et al., 1997 (not all proximal data are plotted).

The dramatic eruption of Gunung Kelud, or Kelut, led to a flurry of images of ash appearing on many social media platforms, including Flickr, Instagram and Twitter. As an experiment in a volcanology class, we sought out images that we could locate on a map, and by classifying the ash deposits as ‘light’, ‘moderate’ or ‘heavy’, generated a very rough contour map of the ash fallout from the eruption. The data show, very crudely, an exponential decay of ash thickness away from the volcano, and allows us to estimate the amount of ash deposited across Java during the eruption. Our current estimate is that the eruption may have deposited the equivalent of 0.2 – 0.3 cubic km of magma across the region. There are considerable uncertainties in this value, but it does confirm that the 2014 eruption was indeed substantial, rating as a Magnitude 4 (VEI 4) event.

Fuller details can be found in a preliminary report: Ash fallout from the 2014 Kelut eruption.

The eruption of Kelut, Java, February 2014

Image of the ash plume from Kelut, drifting across the Indian Ocean on 14th Feb, 2014. NASA Earth Observatory image by Jesse Allen, using data from the Land Atmosphere Near real-time Capability for EOS (LANCE).

Image of the ash plume from Kelut, drifting across the Indian Ocean on 14th Feb, 2014.
NASA Earth Observatory image by Jesse Allen, using data from the Land Atmosphere Near real-time Capability for EOS (LANCE).

I have used storify.com to put together a synopsis of the February eruption of Kelut, Java, Indonesia. There are some additional links to more detailed posts and related information below.

Related posts

Collections on Storify

Links for further information on activity and monitoring

The eruption of Kelut, Gunung Kelud, Java, February 2014

The dramatic eruption of Gunung Kelud (Kelut volcano, Java, Indonesia) provides excellent examples both of how quickly information can spread around the world during unfolding volcanic crises; and of the capacity that we now have for tracking and analysing volcanic eruption plumes in near real time.

  1. Kelut is a dangerous volcano with a volatile history, and the lead in to the latest eruption was short. The first images of the eruption from @hilmi_dzi caught the rapid lofting of the plume.
  2. And, about 90 minutes later, also from @hilmi_dzi, the spectacular lightning show that often accompanies ash-rich plumes. In this image, there is also a clear glow from the core of the plume, where the hot volcanic mixture of ash and gas is emerging from the vent.
  3. Earth pic of the day. Indonesia’s Mount #Kelud volcano erupts with static discharge lightning. Credit: @hilmi_dzi pic.twitter.com/ymG2ItUfEq
  4. Indonesia is well prepared for volcanic emergencies, with over 130 active volcanoes, and major recent eruptions at both Sinabung (on Sumatra) and Merapi (on Java); a theme picked up both by the Indonesian press, and in social media posts.
  5. Front Page, Feb. 15: Mt. Kelud’s eruption displaces thousands, halts flights, spews ash pic.twitter.com/zQXyaF3b9H
  6. Volcanic ash in Yogyakarta in 2010 (eruption of Merapi) and 2014 (eruption of Kelut)
  7. #jogja Foto Perbandingan dampak hujan Abu Vulkanik di tugu ,Merapi 2010 Kelud 2014 pic.twitter.com/jnUkmMJypa via @JogjaMedia| @LensaJogja
  8. Explosive volcanic eruptions pose a significant threat not only to communities living around the volcano, but also to air traffic. In this case, the Volcanic Ash Advisory Centre in Darwin, Australia, were quick to respond with forecasts of the likely spread of the ash in the atmosphere.
  9. Estimated extent and prediciton of the ash plume (VAAC Darwin). pic.twitter.com/XPchidd6Bt
  10. In the early stages of an eruption it can be quite hard to gauge how high the ash has been lofted in the atmosphere; and this is also something that can change quickly depending on the strength of the eruption.
  11. Kelut #volcano in Java is erupting – Darwin VAAC reports ash cloud to 15 km altitude  http://www.bom.gov.au/products/IDD65295.shtml 
  12. #Darwin VAAC says volcanic ash plume observed to FL550 500NM WSW of Mt Kalud, Java. Some flts in region cnld/diverted pic.twitter.com/VLXd4i8XCB
  13. For an explosive eruption of this scale, remote-sensing measurements from satellites can very quickly provide the cofirmation needed on the ground in terms of the scale of the eruption, and the location of the ash cloud. As explained on the NASA Earth website, satellites first detected the eruption at 11.09 pm local time (20 minutes before @hilmi_dzi‘s first photo, above); and at 12.30 am (local) the Visible Infrared Imaging Radiometer Suite (VIIRS) on the Suomi NPP satellite captured an image of the top of the plume rising above the clouds.Shortly after, a laser-ranging instrument (Cloud-Aerosol Lidar, CALIOP) flew over on board the CALIPSO satellite, providing the first direct evidence that the plume top had reached between about 20 km and 26 km height.
  14. A satellite recorded ash from Mt. Kelut at an altitude of 20 kilometers (12 miles).  http://1.usa.gov/1gFqkY5  pic.twitter.com/J1Q7OPvhV9
  15. Peter Webley expands on this in a blog post, showing a reconstruction of the plume in cross section.
  16. Volcanic Activity in the North Pacific and beyond: Visualizing the Kelut Volcano eruption cloud in Go…  http://volcanodetect.blogspot.com/2014/02/visualizing-kelut-volcano-eruption.html?spref=tw 
  17. Volcanologists and atmospheric scientists are quite interested to know how high eruption plumes reach because that information tells them both about the strength of an eruption (the stronger the eruption, the higher the plume); and also about the potential of an eruption to have an influence globally, which is usually thought to require an eruption to loft material into the stratosphere.  In this case, it appears that some of the plume did intrude into the stratosphere; but in fact the first look at the potential gas emissions (in particular sulphur dioxide) suggests that these are actually rather small.
  18. SO2 from #Kelud drifts over Indian Ocean.
    SO2 mass is modest – no measurable climate impact expected #climatechange pic.twitter.com/CSaxanK1sH
  19. Perhaps of more (academic) interest to scientists is the structure of the expanding ash cloud itself – notice the ripples visible in the infra-red image above.
  20. CALIPSO lidar data for #Kelud eruption show nice gravity waves in the umbrella cloud at ~19 km altitude pic.twitter.com/V3yqFGb4YP
  21. The eruption also literally sent soundwaves around the globe, with an infrasound signal detected by the global Comprehensive Test-ban Treaty Organisation array, as well as other infrasound networks – a promising tool in monitoring activity at the world’s active volcanoes.
  22. Global infrasound from the 13 February 2014 Kelut Volcano eruption in Java!  http://newsroom.ctbto.org/ 
  23. Earth Observatory of Singapore gets a sound check for their new infrasound station from #Kelud/#Kelut volcano. Will improve SE Asia coverage
  24. Across Java, of course, the eruption has caused substantial disruption with reports of over 100,000 people being evacuated, a number of fatalities, and disruption to transport networks due to the fallout of ash across a wide portion of Java. The tweets and images below capture just a little of the scale of the misery caused by this event.
  25. Airport to and from Surabaya, Yogya, Solo, Bandung are still closed until 6:00 am tomorrow due to volcanic eruption of Mt Kelud, East Java.
  26. Ash covers this airplane from the eruption of Mount Kelud near Java in Indonesia. #737 #Boeing pic.twitter.com/5HSDGN8dmm
  27. Volcanic ash covers a plane at Yogyakarta airport, about 200 km west of the Mount Kelud volcano on Java pic.twitter.com/TvDw7H9l8H
  28. Juanda Airport in Surabaya after eruption of Mt. Kelud, 1 of 4 airports on Java reportedly closed pic.twitter.com/4AxxVk8Kox via @madhannnn
  29. @AP Sat, Feb 15th. Volcanic ashes of Mt. Kelud, at Adisucipto Int’l Airport in Yogyakarta, Java, Indonesia. pic.twitter.com/NizhwiHyh6
  30. Everyting is grey.. I can’t see the way..
    Volcano ash because of Mt.Kelud eruption
    #grey #Yogyakarta http://instagram.com/p/kd9QFsCW9e/ 
  31. Like a dead city.. taken from upstairs.. the trees and houses are covered by the ash of Mt. Kelud…  http://instagram.com/p/keDmSiCBaa/ 
  32. Suasana Puri Timoho Asri Baru II pasca hujan abu vulkanik Gunung Kelud . Hujan salju man 😀 #nofilter  http://instagram.com/p/keK63PyzXb/ 
  33. More ash, this time from Mount Kelud in Indonesia, in today’s #bikepic from Getty Images. pic.twitter.com/tBrQldxhkP
  34. The eruption of Mount Kelud in Malang, on the island of Java in Indonesia
    A duck walks through the mud and ash. pic.twitter.com/bP6vYFekzA

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The Kameni islands, Santorini, Greece

A glimpse of the spectacular Kameni or ‘burnt’ islands of Santorini, Greece from the air reveals in intricate detail the overlapping lava flows, explosion craters and fields of volcanic ash from which the islands have been built in successive eruptions over the past 2000 years, and more.

Air photo mosaic of the Kameni island of Santorini, based on images taken during a 2004 NERC Airborne Research and Survey Facility campaign

Air photo mosaic of the Kameni island of Santorini, based on images taken during a NERC Airborne Research and Survey Facility campaign in 2004, and published later in an open access paper (Pyle and Elliott, 2006). A high resolution (340 Mb) version of this image is now available from figshare.

Of course, what we can see from the air is just the literal ‘tip’ of the present-day volcano which has grown up within the flooded caldera of Santorini since the last major explosive eruption, the Minoan eruption of ca. 1600 BC. Historical records and accounts from as far back as the Greek geographer Strabo, suggest that there have been at least ten eruptions in and around the Kameni islands since 197 BC. It is quite likely that there have been more that either weren’t noticed (because they were underwater), or that have been forgotten about with the passage of time. The present day the Kameni islands have a volume of about 3 cubic kilometres (of lava), measured from the sea-floor, and must have grown up at an average rate of about 1 million cubic metres per year since the Minoan eruption.

Data sources.

The high resolution version of the composite aerial photograph of the Kameni islands is available to download from figshare,

Link to the original paper: DM Pyle and  JR Elliott, 2006, Quantitative morphology, recent evolution and future activity of the Kameni islands volcano, Santorini, Greece, Geosphere 2 (5), 253-268  [Open Access]

Related web pages and posts.

A blog post from August 2013 – ‘Santorini: a volcano in remission

Some web pages introducing the volcanic history of the Kameni islands.