Sunday, 7 October 2012

Volcanism Update by Request

I got a question about possible volcanic activity, what implications it can have on the u.s and some analogs to support this.

In response I don't see any major eruptions right now besides a small eruption in guatemala by the name of mount fuego. Heres a quote from the smithsonian weekly report "Frequent vigorous historical eruptions have been recorded at Fuego since the onset of the Spanish era in 1524, and have produced major ashfalls, along with occasional pyroclastic flows and lava flows. The last major explosive eruption from Fuego took place in 1974, producing spectacular pyroclastic flows visible from Antigua." I don't think fuego is a threat to the global climate right now because it is only spewing a small amount of ash and its only reaching 1.1km at the most which isn't high enough into the atmosphere to create any disruption to the weather patterns. The ash will eventually get precipitated out within weeks. Besides that all is quite right now. Some other analogs which depict the global cooling effect volcanoes have on the globe include 93-94,94-95,95-6 which followed the mount pinatubo eruptions causing major global cooling as well as a frigid north america.

 There was also the winters of 83-84,84-85 and 85-86 which were frigid across the u.s caused by the major eruption of Mount St Helens. Take note of the +PNA and negative EPO pattern across north america which set up cold winters as well as the high latitude blocking.
Take a look at the global cooling that occurred as a result of so2 that was spewed into the stratosphere  adn converted to volcanic aerosols deflecting incoming solar radiation from the sun. This favours high latitude blocking. This is common in major high latitude volcanoes especially in low solar regimes as we are currently experiencing. Tropical volcanoes do the opposite and cause short term cooling and long term warming because it weakens the easterlies in the pacific and creates an el nino (producing long term global warming). Notice the warming of the last decade caused by little volcanic aerosol's in the stratosphere.

Something very interesting is Katla, a neighbouring volcano to Eyjafjallajökull which some say is overdue for a major eruption. There are signs of higher activity between the much larger and more deadly katla in iceland which may be a sign of an upcoming eruption. Eruption from katla occur on average every 60 years and oddly enough have occurred within months after its neighbouring Eyjafjallajökull erupts. Last July, a flood of water burst from beneath the ice cap on top of Katla, washing away a bridge. This indicates that an extra pulse of heat reached the base of the ice. Since then, there have been erratic movements of the surface of the volcano, measured by precise GPS instruments, and bursts of high earthquake activity beneath Katla’s caldera. These observations imply that magma has risen to shallower depths. Katla’s eruption in 1918 produced five times as much ash as the 2010 Eyjafjallajökull one. A major eruption could result in large parts of Iceland being flooded as snow and ice melted; significant poisoning of Icelandic agriculture; destruction of property; and, of course, the grounding of aircraft across Europe. Also major global cooling will be produced for years to follow if this threat comes to fruition. 


  1. Very interesting look at volcanism and it's effects on weather, thank you! I once read a theory (Russian?) that large CMEs (coronal mass ejections) from the sun, besides causing aurora, can increase the likelyhood of earthquakes, and I would guess, volcanic activity. The idea was that the incoming energy acting on the earth's magnetic field causes the magma to heat up, both increasing currents and slightly expanding the crust, loosening the plates.

  2. Thank you for this answer to my question!

    It seems to me that here you omit in this post the suggestion from your winter outlook that the 2009 eruptions could play toward colder winters starting this year. You wrote (I'll quote for those who didn't read the whole winter outlook):
    "Due to the volcanos that recently erupted in 2009 we may see some strong cooling showing up this winter or the following winters as a result. . . In the winter of 2009-10 we saw Mt. Redoubt in Alaska, Sarychev in Russia and Eyjafjallajökull in Iceland. If we do the math we can see that as history is shown to repeat itself we will see a lot of cold showing up in north america in the winters of 2012-13, 2013-14 and 2014-15."
    The aerosol optical thickness is interesting and suggestive of a relationship. Is there a way to get the most recent and current data (last four years)?

    1. Glad to answer your question! This link might be what you are looking for:
      or this:

    2. Well I'm wondering if there is data for aerosol optical thickness for 2008-2012. Doesn't look like it on those sites.

    3. This is a good visual representation from nasa:;jsessionid=D436A19AA4B6317EF12B306FB610EBF7?duration=day&startMonth=&startDay=&startYear=&endMonth=&endDay=&endYear=&sourceDatasetId=MODAL2_AER_OD&maxLat=&minLon=&maxLon=&minLat=&size=full&palette=rgb&format=JPEG&w=&h=&ssn=&ssw=&sse=&sss=&datasetId=MODAL2_E_AER_OD

      Right now, I can't find the actual data but i will let you know as soon as i find it.