Objectives Volcano monitoring as a strategy to reduce risk due to volcanic eruption Objectives Understand how geologists monitor volcanoes. Understand what data indicate a volcano is awakening from dormancy, and what data indicate that an actual eruption is imminent. Understand what factors determine whether volcano monitoring can be effective in mitigating risk to people and property.

Ground Deformation Seismicity Gas Emission Tilt (tiltmeters) Prework Monitoring volcanoes Ground Deformation Tilt (tiltmeters) High precision GPS Movement of stations Baseline length changes Seismicity Gas Emission http://www.youtube.com/watch?v=sNYQkxxd_0Q http://www.youtube.com/watch?v=nlo-2JoNHrw http://www.youtube.com/watch?v=owk4fWbw4qM

Ground Deformation Seismicity Gas Emission Tilt (tiltmeters) Prework Monitoring volcanoes Ground Deformation Tilt (tiltmeters) High precision GPS Movement of stations Baseline length changes Seismicity Gas Emission http://www.youtube.com/watch?v=sNYQkxxd_0Q This activity emphasizes the circled methods of volcano monitoring. http://www.youtube.com/watch?v=nlo-2JoNHrw http://www.youtube.com/watch?v=owk4fWbw4qM

Monitoring volcanoes Thought experiment

A volcano, with five GPS stations on the surface of the volcano (blue triangles) that continually record their locations. km     Topographic shaded relief map of Mount Gordon, Alaska Credit: Alaska Volcano Observatory, the U.S. Geological Survey, BigTopo 7, AllTopo 7 Image source: http://www.avo.alaska.edu/images/image.php?id=2935 Accessed December 2013

1. Imagine that a body of magma intrudes below the summit of the volcano, without erupting. Predict how the GPS stations will move. km       Topographic shaded relief map of Mount Gordon, Alaska Credit: Alaska Volcano Observatory, the U.S. Geological Survey, BigTopo 7, AllTopo 7 Image source: http://www.avo.alaska.edu/images/image.php?id=2935 Accessed December 2013  

Eruption! Topographic shaded relief map of Mount Gordon, Alaska km       Topographic shaded relief map of Mount Gordon, Alaska Credit: Alaska Volcano Observatory, the U.S. Geological Survey, BigTopo 7, AllTopo 7 Image source: http://www.avo.alaska.edu/images/image.php?id=2935 Accessed December 2013  

2. The eruption is over. Predict how the GPS stations will move. km       Topographic shaded relief map of Mount Gordon, Alaska Credit: Alaska Volcano Observatory, the U.S. Geological Survey, BigTopo 7, AllTopo 7 Image source: http://www.avo.alaska.edu/images/image.php?id=2935 Accessed December 2013

Anatomy of an eruption – 2010 events at Eyjafjallajokull Part 2: Mitigating the Risk Anatomy of an eruption – 2010 events at Eyjafjallajokull Eyjafjallajökull Review the tectonic setting of Iceland and Eyjafjallajokull. Google Earth Image with data from Landsat, IBCAO, SIO, NOAA, U.S. Navy, NGA, GEBCO. Accessed December 2013. Volcano locations from the Global Volcanism Program Google Earth kmz file, used with permission from Elizabeth Cottrell, Curator, Research Geologist, and Director of the Global Volcanism Program, Department of Mineral Sciences, National Museum of Natural History, Smithsonian Institution. Accessed December 2013.

Eyjafjallajökull 2010 eruption of “Island Mountain Glacier” (term actually refers to the ice cap atop the volcano) Date of photo: March 25, 2006 Last active: 1821-1823 We will be following events at Eyjafjallajokull via monitoring of earthquake and ground motion. The name actually refers to the ice cap on top of the volcano. The area is unpopulated. Before 2009, the area had been seismically quiet for 13 years, and ground motion was stable. Photo credit: "Iceland Eyjafjallajökull from Sólheimajökull" by Advanstra - Own work. Licensed under Creative Commons Attribution-Share Alike 3.0 via Wikimedia Commons. Source: http://commons.wikimedia.org/wiki/File:Iceland_Eyjafjallaj%C3%B6kull_from_S%C3%B3lheimaj%C3%B6kull.JPG#mediaviewer/File:Iceland_Eyjafjallaj%C3%B6kull_from_S%C3%B3lheimaj%C3%B6kull.JPG Accessed December 2013. Before 2009, the area had been seismically quiet for 13 years, and ground motion was stable. In 2009, small earthquakes began to be detected underneath the volcano.

March 20: Eruption! x x DURING THE ERUPTION Eyafyallajokull x On March 20, 2010 fissures opened up on the east flank of the volcano and lava fountains erupted, generating lava flows. Photo credit: "Fimmvorduhals 2010 03 27 dawn" by Henrik Thorburn, licensed under Creative Commons Attribution 3.0 via Wikimedia Commons. Source: http://commons.wikimedia.org/wiki/File:Fimmvorduhals_2010_03_27_dawn.jpg#mediaviewer/File:Fimmvorduhals_2010_03_27_dawn.jpg Accessed December 2013. Map with GPS station locations Credit: Iceland Meteorological Survey; University of Iceland, FutureVolc project (http://futurevolc.hi.is/) Image source: https://notendur.hi.is/runa/eyja_gps.html Accessed December 2013. Used with permission (Sigrun Hreinsdottir). UP Non-explosive eruption begins: Fissures open on flank 10 km east of summit, with lava fountaining and lava flows.

Lava fountain Lava flow During the 2010 eruption of Eyjafjallajökull, the nearby second fissure on Fimmvörðuháls erupts. Lava flows north, turning snow into steam. Over the next few weeks, activity waned and then… Photo credit: Henrik Thorburn (Creative Commons Attribution 3.0 Unported license) Source: http://en.wikipedia.org/wiki/File:Fimmvorduhals_second_fissure_2010_04_02.JPG Accessed December 2013. Lava flow

DURING THE ERUPTION April 14: More eruption! x Eruption migrates to summit, with much greater explosivity and volume! Eyafyallajokull x x x Photo Credit: U.S. Geological Survey, Department of the Interior, USGS, Photographer: Oddur Sigurðsson, Photographer Organization: Iceland Meteorological Office Source: http://gallery.usgs.gov/photos/09_18_2013_j41Pht6GGb_09_18_2013_3#.VA6hL0gwJEz Accessed December 2013. Map with GPS station locations Credit: Iceland Meteorological Survey; University of Iceland, FutureVolc project (http://futurevolc.hi.is/) Image source: https://notendur.hi.is/runa/eyja_gps.html Accessed December 2013. Used with permission (Sigrun Hreinsdottir). UP

April 17 “NASA's Aqua satellite passed over Iceland's Eyjafjallajokull Volcano (top left) on May 10 at 13:25 UTC (9:25 a.m. EDT). A visible image taken from the Moderate Imaging Spectroradiometer (MODIS) Instrument that flies aboard the satellite showed the ash plume streaming in a straighter, more steady path than the day before, indicating winds were stronger than they were May 9. The ash plume was moving in a south-southeasterly direction over the Northern Atlantic Ocean. Farther south in the image the ash plume became partially obscured by higher clouds (white). By May 10, the ash had reached North Africa, Turkey and Morocco.” Photo and caption credit: NASA Goddard / MODIS Rapid Response Team. Source: http://www.nasa.gov/topics/earth/features/iceland-volcano-plume-archive1.html Accessed December 2013.

Image credit: "Disruptions at Leeds Bradford Airport during the eruptions of Eyjafjallajökull" by Flickr user:katjung - http://www.flickr.com/photos/katjung/4531865356/. Licensed under Creative Commons Attribution-Share Alike 2.0 via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:Disruptions_at_Leeds_Bradford_Airport_during_the_eruptions_of_Eyjafjallaj%C3%B6kull.jpg#mediaviewer/File:Disruptions_at_Leeds_Bradford_Airport_during_the_eruptions_of_Eyjafjallaj%C3%B6kull.jpg Air travel over Europe shut down for six days; 95,000 flights cancelled.

Explosive phase April 14-May 24 April 14-20 250 meters of the ice cap melted in 4 hours, and interaction with meltwater caused explosive activity and produced lots of ash. Glacial meltwater destroyed roads, including the major coastal highway, and caused evacuations. April 20-May 3  Lava flow in northern part of the glacier melted ice sufficient to form a 150m-deep ice depression at the surface. May 4-May 18 Most vigorous explosive phase, producing >30 kilotons of SO2, 150 kilotons of CO2 and a huge ash plume up to 10km high that stratospheric winds carried across Europe. May 19-May 24  Eruption waned and plume gradually declined. Volcanic gas emissions slowed until the eruption stopped. https://www.geolsoc.org.uk/Geoscientist/Archive/April-2011/Online-Special-Rock--ice-Eyjafjallajkull-and-Climate-Change

Eruption Consequences European airspace disrupted; shut down completely for 6 days; ~95,000 flights cancelled. $2 billion lost by airlines. Travel, commerce, tourism disrupted worldwide. 800 people, and dozens of farms evacuated (and in some cases abandoned due to fluorine-containing ash, poisonous to grazing animals). Damage to roads by glacial floods. Silting up and and subsequent dredging of rivers. No deaths, injuries or ash-related illnesses

Preparedness/Response The Icelandic Meteorological Office (IMO) http://en.vedur.is/ monitors weather, earthquakes, volcanoes, stream flow, and avalanche conditions. During Eyjafjallajokull events, the IMO worked closely with the Civil Protection Department (CPD) of the National Commissioner of the Icelandic Police Institute of Earth Sciences at the University of Iceland London Volcanic Ash Advisory Centre of the British Meteorological Office These agencies cooperate to: Monitor, collect and analyze data Issue timely warnings Put emergency/crisis procedures and action plans into action Review of the extensive monitoring system and cooperation between various agencies that lead to timely action which mitigated damage to the population.

Ground Deformation Seismicity Gas Emission Tilt (tiltmeters) Monitoring volcanoes Ground Deformation Tilt (tiltmeters) High precision GPS Movement of stations Baseline length changes Seismicity Gas Emission We will now backtrack, and take a detailed look at ground motion and seismicity associated with this eruption, starting with motion of GPS stations on and around the volcano.

x Map of study area showing Credit: Iceland Meteorological Survey; University of Iceland, FutureVolc project (http://futurevolc.hi.is/) Image source: https://notendur.hi.is/runa/eyja_gps.html Accessed December 2013. Used with permission (Sigrun Hreinsdottir). Map of study area showing the summit of Ejafjallajokull (x) and the locations of GPS stations.

x Map with GPS station locations used with permission (via email) from Sigrun Hreinsdottir. Data source: FutureVolc project (http://futurevolc.hi.is/) accessed at https://notendur.hi.is/runa/eyja_gps.html 3. PREDICTED MOTION: Describe how you think your station will move before, during and after an eruption at Eyjafjallajokull. Draw arrows on the map indicating the motion(s) you predict and describe your predictions. Be sure to indicate compass direction AND the vertical component (UP or DOWN) for each stage of motion.

Ok, let’s look at some data – x Map with GPS station locations used with permission (via email) from Sigrun Hreinsdottir. Data source: FutureVolc project (http://futurevolc.hi.is/) accessed at https://notendur.hi.is/runa/eyja_gps.html Ok, let’s look at some data – But first, a reminder about reading and interpreting GPS time series data.

Reading GPS time series: motion is resolved into three components 40 20 -20 -40 80 -80 North East Up northward No N-S movement southward Figure by Laurel Goodell, Princeton University; provided under terms of the Creative Commons Public License 3.0. eastward westward No E-W movement upward No vertical movement downward Time

Test yourself: North East Up 40 20 -20 -40 80 -80 -20 -40 80 -80 North East Up 2009 2010 Test yourself: Which way was this station moving in 2009? Up to the SE Which way was this station moving in 2010? Due north, with no change in the vertical component. N.B. Today we are just interested in the general trend, not fully resolving the direction and rate.

How does the actual motion compare with your predictions? x Map with GPS station locations used with permission (via email) from Sigrun Hreinsdottir. Data source: FutureVolc project (http://futurevolc.hi.is/) accessed at https://notendur.hi.is/runa/eyja_gps.html 4. ACTUAL MOTION Analyze the GPS time series and describe the actual motion of your station before, during and after the eruption. Draw arrows on the map indicating the motion(s) and describe your predictions. Be sure to indicate compass direction AND the vertical component (UP or DOWN) for each stage of motion. How does the actual motion compare with your predictions?

Station GOLA: GPS time series used with permission (via email) from Sigrun Hreinsdottir. Data source: FutureVolc project (http://futurevolc.hi.is/) accessed at https://notendur.hi.is/runa/eyja_gps.html https://notendur.hi.is/~runa/eyja_gps.html

Station SKOG: GPS time series used with permission (via email) from Sigrun Hreinsdottir. Data source: FutureVolc project (http://futurevolc.hi.is/) accessed at https://notendur.hi.is/runa/eyja_gps.html https://notendur.hi.is/~runa/eyja_gps.html

Station STE2: Feb Apr Jun Aug Oct Dec GPS time series used with permission (via email) from Sigrun Hreinsdottir. Data source: FutureVolc project (http://futurevolc.hi.is/) accessed at https://notendur.hi.is/runa/eyja_gps.html https://notendur.hi.is/~runa/eyja_gps.html

Station THEY: GPS time series used with permission (via email) from Sigrun Hreinsdottir. Data source: FutureVolc project (http://futurevolc.hi.is/) accessed at https://notendur.hi.is/runa/eyja_gps.html https://notendur.hi.is/~runa/eyja_gps.html

x Map with GPS station locations used with permission (via email) from Sigrun Hreinsdottir. Data source: FutureVolc project (http://futurevolc.hi.is/) accessed at https://notendur.hi.is/runa/eyja_gps.html 6. After reports from other groups, add arrows indicating the motions of the other stations. Is the behavior of the volcano consistent with the scenario you imagined in the thought experiment? Why or why not?

x Map with GPS station locations used with permission (via email) from Sigrun Hreinsdottir. Data source: FutureVolc project (http://futurevolc.hi.is/) accessed at https://notendur.hi.is/runa/eyja_gps.html 7. Describe the extent to which the stations recover their original, pre-eruption locations (it might be different for different stations). If one or more stations did not recover their original location, why not? What does this imply about the shape of the volcano as a result of the eruption?

Ground Deformation Seismicity Gas Emission Tilt (tiltmeters) Part 2: Mitigating the Risk Monitoring volcanoes Ground Deformation Tilt (tiltmeters) High precision GPS Movement of stations Baseline length changes Seismicity Gas Emission

Animation of earthquake activity underneath Eyjafjallajokull January-May, 2010 http://vimeo.com/10708403 8. Watch this ~1 minute video several times. Describe the earthquake activity, taking note of numbers, depths and locations of epicenters. Note: Date format in upper left is in dd/mm/yyy format The darker the symbol, the deeper the epicenter This visualization shows earthquakes leading up to and during two eruptions in Eyjafjallajökull, Iceland in March and April 2010. Made by Hjalmar Gislason of datamarket.com using data from the Icelandic Meteorological Office (htty://en.vedur.is). Video publically available at http://vimeo.com/10708403 VIMEO videos are freely viewable for non-commercial purposes. See terms of use at http://vimeo.com/terms. 9. Relate the earthquake activity to the GPS data. What do you think is happening at the volcano to cause the observed earthquake activity?

Discussion questions 10 a. What were the indications that the volcano was “waking up” and entering a phase of volcanic activity?

Discussion questions 10 b. What were the indications that the volcano was not only “waking up” but actually about to erupt?

Discussion questions 10 c. How much warning time was there between the first indications that the volcano was “waking up” and the time the volcano actually erupted?

Discussion questions 11. At least for the inhabitants of Iceland (if not the airline companies), this was a low-risk eruption. No lives were lost and property damage was limited. What factors helped account for this?