QU: How can the Eyjafjallajökull eruption in Iceland 2010 be seen as a mega-disaster? AIM: To evaluate the social and economic impacts of a tectonic event in an HIC and the idea of a tectonic 'mega-disaster'. Volcano Explosivity Index... the V.E.I You need to know this scale! The Volcanic Explosivity Index is determined by using one of more of the following critieria: You need to be aware of this scale! Volume of ejecta and height of the eruptive column. ST: A - Using the info on the 12,000m left what was the VEI for 10,500m 11,000m the Ejyafjalljokull 9000m eruption? B - Why might this be 7500m considered unusual for 6000m Iceland? (consider margin 4500m type!) C - Suggest reasons for 3000m the relationship between 1500m 1600m VEI and frequency. 0 1
Eyjafjallajökull is the name of the vast glacier which covers the crater but the mountain ridge containing the volcano itself is simply called Eyjafyoll (Ayuh fyotl). Eyja means island, fyalla or fyjoll means mountain, and jökull means glacier, so the name actually means the island mountain glacier. 2
Iceland - Population density Reykjavik Eyjafjallajökull 100km TASK: a - Describe the population distribution of Iceland and location of Eyjafjallajokul within Iceland. b - With the information from this map alone, and the fact Iceland is on a mantle plume/constructive margin create a hazard profile for Eyjafjallajokul. Use the outline supplied. Assume 2010 HAS NOT happened. 3
Eyjafjallajökull Hazard profile Info to help: The VEI of a typical Icelandic/hot spot volcano is 0-2. Eyjafjallajokull had been dormant for 200 years. Erupting under a glacier means lava often cools quickly and does not travel far. Eyjafjallajokull is a remote volcano. Being under an ice sheet their are only a few isolated communities nearby. The nearest town, Vik, is 50km to the SE and has a population of 360 people. (2016 census) Iceland has some of the most advanced volcano monitoring equipment in the world. Previous Jokulhlaup flow paths (glacier bursts) are well known. 4
How much of a Hazard is Eyjafjallajokull to the local area? 2 Examine the colour copy map of an area of roughly 35km around Eyjafjallajokull. a On your sketch map colour code the areas as dictated by the key. b A disaster is defined as damage to human life and property. Do your best to find and label key infrastructure and settlements or any obvious threat. Mark it on your tracing paper. Remember a major hazard is glacial melt water. (Jokulhlaup). These tend to follow existing drainage channels and streams. You are effectively producing a HAZARD MAP for this area. c Comment on the KEY risk locally. How Isolated dwellings house/farm Church disruptive could an eruption be? Minor un surfaced road Tourist cabin Campsite Main road surfaced Aerodrome light aircraft Guest house Community Hall Ford Ruined building Cave Viewpoint River/stream Area of drained arable farmland Ideas: Isolation levels, density of population, value of land use, predictability of hazards and their direction. d Should the Icelandic government be putting in nation wide defences and procedures for Eyjafjallajokull? Explain your views. Ext: What do the number of ruined buildings indicate about population trends in the area? Why might this be? 5
Key 25km Ice 11-1000m 0-10m N 6
TASK: So did you predict the main dangers? Watch the clip and see. 0:00 3:15 1 Who initially investigated the eruption? 2 What does this tell you about structures and emergency procedures in Iceland? 3 What initial benefit did the eruption bring? 4 What are the properties of Basaltic lava? 5 Why was the eruption location of little concern? 4:59 9.30. 6 What concerns grew about the icecap? 7 Why are glacial outburst floods so dangerous? (Jokulhlaup) 8 List some impacts mentioned. 9 What characterises a Phreatomagmatic eruption? Rising magma is by meltwater. This fragments it into tiny particles of which are high into the atmosphere. 7
Anyone recognise this? Local impacts... As expected and predicted. No loss of life and minimum disruption. Hardly a disaster... 8
Site of road breach 9
So how did this become a tectonic mega event? Today Next lesson 10