Tags: oceanography, phytoplankton, volcanic ash
The eruption of Alaska’s Kasatochi volcano in August 2008 has led to a surge in the population of phytoplankton in the North Pacific, says a paper in Geophysical Research Letters authored by a horde of scientists from institutions in Canada, the USA and the UK, led by oceanographer Roberta C. Hamme of the University of Victoria, British Columbia. An unusual storm system meant that the ash deposited by the volcano was transported across a very wide area of the north-eastern Pacific, and the iron content encouraged the growth of phytoplankton (for which iron is a key nutrient), producing one of the largest plankton blooms ever recorded in this region. Scientists have recently suggested that volcanic ash fertilization of the ocean in this way can occur, but, as Professor Hamme notes in the very useful summary of the Kasatochi paper she has made available as a PDF on her website (wish more scientists would do that), this is the first time conclusive evidence has been obtained to support the hypothesis.
Because phytoplankton (which are the basis of oceanic and freshwater food chains) consume carbon dioxide and release oxygen, seeding the oceans with iron to encourage their growth has sometimes been suggested as a means of diminishing atmospheric CO2. However, the evidence of the naturally-occurring Kasatochi seeding episode is that the process is not very efficient and that it would take a lot of iron to make even a small difference.
- Roberta C. Hamme et al. ‘Volcanic ash fuels anomalous plankton bloom in subarctic northeast Pacific’, Geophysical Research Letters, 37 (2010), doi:10.1029/2010GL044629. [abstract]
How volcanoes feed plankton – ScienceNow, 5 October 2010
Effects of volcanic eruption dash promising global warming theory – Globe and Mail, 5 October 2010
Volcano ‘seeded’ ocean bloom – UPI.com, 6 October 2010
Life returning to Kasatochi 31 August 2009Posted by admin in Alaska, Kasatochi.
Tags: Alaska, Kasatochi, United States, volcanic eruptions, volcano research
Life is already returning to the island of Kasatochi in the Aleutians, blanketed with ash and left bleak and barren by the surprise eruption of its eponymous volcano in August 2008. A scientific team is revisiting the island to look at how it is responding to the eruption, the Anchorage Daily News is running a series of reports on their work, written by University of Alaska Geophysical Institute Science Writer Ned Rozell.
The latest report describes the way in which life is ‘inching its way back to Kasatochi’. The birds are gone and ash outwash from the island is disrupting kelp growth in the surrounding ocean, but nineteen species of plant have been found springing back to life on the island, along with an insect or two and some tough invertebrates: ‘The smallest and luckiest of life forms clung to natural bunkers within the island, and mats of plant roots were buried quickly enough to withstand the heat of the eruption flows’.
After eruption life inching its way back to Kasatochi – Anchorage Daily News, 29 August 2009
A volcanic miscellany: Ibu, Toba, Kasatochi, Cotopaxi 21 August 2009Posted by admin in Alaska, Ecuador, Ibu, Indonesia, Kasatochi, Toba, United States, volcano tourism.
Tags: Cotopaxi, Ibu, Kasatochi, supervolcanoes, Toba, volcanism and climate, volcano research, volcano tourism
Catching up with some volcanic bits and bobs that have been hanging around on my desktop/in my inbox/on little pieces of paper in my pocket for the last couple of weeks:
Heightened alert at Ibu. The alert level for the Indonesian volcano Ibu on the island of Halmahera was raised to level 3 (orange/siaga) on 5 August. The last increase in alert level, from 1 (green) to 2 (yellow/waspada), was less than a month earlier, on 15 July. Eruptions of incandescent material accompanied by elevated seismicity occurred with increasing frequency at the end of July. Meanwhile, the lava dome continues to grow. Some very nice pictures of the dome from August 2007 can be found in this Flickr collection (thanks to Volcanism Blog reader Bruce S. for letting me know about this).
Weather wonders and supervolcanoes. Randy Cerveny, geographical sciences professor at Arizona State University, has a new book out called Weather’s Greatest Mysteries Solved! (the exclamation mark is, apparently, part of the title) which looks at the role of the weather in Earth’s prehistory and history, from the extinction of the dinosaurs to the Dust Bowl of the 1930s via the end of the Mayan civilization and the parting of the Red Sea. One chapter is devoted to the Toba eruption of about 74000 years ago, which may (or may not) have brought about the near-extinction of humanity. This topic naturally leads to speculation about possible future ‘supervolcano’ eruptions and the potential threat posed by Yellowstone: ‘It’s overdue’, says Prof. Cerveny, but ‘I don’t think it’s a run into the night screaming kind of thing yet, but if it were to happen civilization as we know it would probably break down’. He also has a nice message of humility for humanity, pointing out that however much ‘We like to think we are masters of our fate … the thing about climate is that there are simply a lot of things we can’t control or even begin to control or totally understand’.
‘Our island blew up’. The August 2008 eruption of Kasatochi volcano in the Aleutians brought an abrupt end to scientific fieldwork being carried out there by two U.S. Fish & Wildlife Service biologists: ‘our island blew up’, is the deadpan observation in their research report. Today Kasatochi, formerly green here and there, is black and barren, and about 32 percent larger than it was before the eruption. A scientific team is revisiting the island to assess the aftermath of the event, and will be accompanied by a reporter from the Alaska Daily News who will file regular reports on their researches.
Music and dance at Cotopaxi. It’s 34 years since the Cotopaxi National Park was created around Cotopaxi volcano in Ecuador, and local communities have been celebrating the anniversary with music and dance, reports El Comercio. The Ecuadorian Minister for the Environment has been at the celebrations, and the locals have taken the opportunity to lobby her for more support and funding for the park and the people who live in and around it. The Parque Nacional Cotopaxi is one of Latin America’s top tourist attractions, receiving more than 100,000 visitors per year.
Kasatochi sunsets 5 September 2008Posted by admin in Alaska, eruptions, Kasatochi, United States, volcano culture.
Tags: Alaska, Kasatochi, volcanic eruptions, volcano culture
The eruption of Kasatochi volcano in the Aleutian Islands on 7 August injected a very large amount of ash and gas into the atmosphere, including reportedly the largest stratospheric sulphur dioxide cloud since the eruption of Cerro Hudson in 1991. Kasatochi’s aerosols are now producing dramatic and beautiful sunsets across the northern hemisphere.
UPDATE: Dave Schumaker has a new post on Kasatochi today (6 September) at Geology News which includes many wonderful images of the recent volcanic sunsets: Kasatochi Eruption and Sunsets.
Red skies and volcanoes – EarthSkyBlogs, 31 August 2008
Volcano sunsets – SpaceWeather.com, 1 September 2008
Twilights of Europe – The Times, 2 September 2008
Volcano’s eruption colors world’s sunsets – LiveScience, 3 September 2008
Sulphur dioxide far and wide 14 August 2008Posted by admin in Alaska, eruptions, Kasatochi, natural hazards, United States.
Tags: Alaska, Kasatochi, natural hazards, United States, volcanic eruptions
The NASA Earth Observatory has published a rather striking image today showing the spread of the sulphur dioxide cloud released by Kasatochi since it began erupting on 8 August. The image, captured by the Ozone Monitoring Instrument on NASA’s Aura satellite on 12 August, shows the gas looping counter-clockwise across the Pacific Ocean and spreading across Canada and the United States.
The image as shown above has been cropped slightly to fit in here at The Volcanism Blog. To see the original image with an extended explanatory caption, click here. Take some time to explore the NASA Earth Observatory: it is a wonderful resource, for volcanoes and much more.
The volcano domino effect? 13 August 2008Posted by admin in Alaska, blogs, Cleveland, eruptions, Kasatochi, Okmok, United States.
Tags: Alaska, Cleveland, Kasatochi, Okmok, United States
Three volcanoes are currently active in the Aleutian Islands: Okmok, Cleveland and Kasatochi. Chris Rowan at Highly Allocthonous ponders on this near-simultaneous eruption of three volcanoes in the same neighbourhood in an interesting post and asks. ‘Could the eruption of one have triggered the others?’ Answer: ‘no’. Disappointing news for volcanic chain-reaction catastrophists everywhere.
Kasatochi eruption – satellite images 13 August 2008Posted by admin in activity reports, Alaska, eruptions, Kasatochi, United States.
Tags: Alaska, Kasatochi, United States, volcanic eruptions
Kasatochi volcano in the Aleutian Islands erupted on 7 August: full information about this dramatic and powerful eruption can be found at the Alaska Volcano Observatory and via the coverage at Eruptions.
The images above come from the NASA Earth Observatory site (click on each image to go to the original Earth Observatory page for that image). The upper image, from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite, shows Kasatochi’s brown eruption plume swirling counterclockwise from the volcano on 8 August 2008. The lower image comes from the Ozone Monitoring Instrument on NASA’s Aura satellite and indicates the levels of sulphur dioxide released by the Kasatochi eruption. The image was captured on 10 August 2008. The NASA caption for this image notes that the Kastachi eruption cloud contained about 1.5 million tons (1.36 million tonnes) of sulphur dioxide, and is one of the largest volcanic SO2 clouds scientists have tracked since Chile’s Hudson volcano erupted in 1991.