1. 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.

2. 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

3. 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
This activity emphasizes the circled methods of volcano monitoring.

4. Monitoring volcanoes
Thought experiment

5. 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:
Accessed December 2013

6. 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:
Accessed December 2013

7. Eruption! Topographic shaded relief map of Mount Gordon, Alaskakm
Topographic shaded relief map of Mount Gordon, Alaska
Credit: Alaska Volcano Observatory, the U.S. Geological Survey, BigTopo 7, AllTopo 7
Image source:
Accessed December 2013

8. 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:
Accessed December 2013

9. 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.

10. 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:
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: 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.

11. 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 dawn" by Henrik Thorburn, licensed under Creative Commons Attribution 3.0 via Wikimedia Commons. Source: Accessed December 2013.
Map with GPS station locations
Credit: Iceland Meteorological Survey; University of Iceland, FutureVolc project (
Image source:
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.

12. 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: Accessed December 2013.
Lava flow

13. 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: Accessed December 2013.
Map with GPS station locations
Credit: Iceland Meteorological Survey; University of Iceland, FutureVolc project (
Image source:
Accessed December 2013.
Used with permission (Sigrun Hreinsdottir). UP

14. 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:
Accessed December 2013.

15. Image credit: "Disruptions at Leeds Bradford Airport during the eruptions of Eyjafjallajökull" by Flickr user:katjung - Licensed under Creative Commons Attribution-Share Alike 2.0 via Wikimedia Commons -
Air travel over Europe shut down for six days; 95,000 flights cancelled.

16. Explosive phase April 14-May 24
April 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.

17. 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

18. Preparedness/Response
The Icelandic Meteorological Office (IMO) 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.

19. 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.

20. x Map of study area showing
Credit: Iceland Meteorological Survey; University of Iceland, FutureVolc project (
Image source:
Accessed December 2013.
Used with permission (Sigrun Hreinsdottir).
Map of study area showing
the summit of Ejafjallajokull (x) and the locations of GPS stations.

21. x
Map with GPS station locations used with permission (via ) from Sigrun Hreinsdottir.
Data source: FutureVolc project ( accessed at
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.

22. Ok, let’s look at some data – x
Map with GPS station locations used with permission (via ) from Sigrun Hreinsdottir.
Data source: FutureVolc project ( accessed at
Ok, let’s look at some data –
But first, a reminder about reading and interpreting GPS time series data.

23. Reading GPS time series: motion is resolved into three components40 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

24. 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.

25. How does the actual motion compare with your predictions?x
Map with GPS station locations used with permission (via ) from Sigrun Hreinsdottir.
Data source: FutureVolc project ( accessed at
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?

26. Station GOLA:
GPS time series used with permission (via ) from Sigrun Hreinsdottir.
Data source: FutureVolc project ( accessed at

27. Station SKOG:
GPS time series used with permission (via ) from Sigrun Hreinsdottir.
Data source: FutureVolc project ( accessed at

28. Station STE2:
Feb
Apr
Jun
Aug
Oct
Dec
GPS time series used with permission (via ) from Sigrun Hreinsdottir.
Data source: FutureVolc project ( accessed at

29. Station THEY:
GPS time series used with permission (via ) from Sigrun Hreinsdottir.
Data source: FutureVolc project ( accessed at

30. x
Map with GPS station locations used with permission (via ) from Sigrun Hreinsdottir.
Data source: FutureVolc project ( accessed at
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?

31. x
Map with GPS station locations used with permission (via ) from Sigrun Hreinsdottir.
Data source: FutureVolc project ( accessed at
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?

32. 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

33. Animation of earthquake activity underneath Eyjafjallajokull January-May, 2010
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
VIMEO videos are freely viewable for non-commercial purposes. See terms of use at
9. Relate the earthquake activity to the GPS data. What do you think is happening at the volcano to cause the observed earthquake activity?

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

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

36. 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?

37. 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?