REYKJAVIK

Vestmannaeyjar

LangjökullHofsjökull

Selfoss

Höfn

Borgarnes

Katla

HeklaKe�avik

KopavogurGrindavik

Eyjafjallajökull

EldfellSurtsey

Stykkishólmur

Húsavik

Akureyri

Dalvik

Atlantic Ocean

Öræfajökull

Bárðarbunga

GrímsvötnVatn

ajökull

Blanda

Pjórsá

Héraðsvötn

Jökulsa á Fjöllum

Arctic Circle

The threat from

celand – ‘land of fire and ice’ – has always been regarded as a geographer’s paradise. Situated just below the Arctic Circle, it is Europe’s most western landmass. Despite its small size (roughly the same area as Ireland, albeit growing by around 5 cm a year as the Eurasian and North American plates continue to pull apart), it captivates the imagination and invites superlatives as ‘a geographical and geological melting pot, with landscapes and features that are ever changing, ever volatile, but always stunning and awe-inspiring’.

For a country with only 340,000 inhabitants (2018), Iceland commands an extraordinary level of attention. From the 2008 banking crisis, to a rich and varied music scene, to its status as an inspirational footballing nation, the country certainly punches above its media weight – and particularly in relation to ‘all things tectonic’.

Eruptions from the recent past The birth of the island of Surtsey (1963–67), and its inspirational story since, deserves mention. It started as a submarine eruption and captured the world’s scientific imagination. Within a decade,

I Eldfell (1973) on Heimaey had erupted, resulting in a major and largely successful effort to slow and control the blocky (aa) lava flow by spraying pumped seawater over its leading edge. Indeed, the relish in which today’s media age might have further ‘hyped’ such events deserves consideration if Eyjafjallajökull (2010) is any measure. This deliciously tongue-twisting textbook staple (pr. Aya-feeyalla-yurkul) had local, national, regional and global impacts. Although there were no fatalities or injuries, the subglacial eruption did cause considerable flooding. However, it was the vast ash cloud spreading over Western Europe that became the main focus of the media: 100,000 flights were cancelled and over 10 million people were left stranded – at a cost to airlines of $1.7 billion.

Consequently, nowadays, signs of awakened volcanic activity anywhere on Iceland are likely to command attention beyond the ‘normal’ insatiable desire of the tabloid press and social media for sensational science stories. This is particularly the case if there are reports of increased seismic activity and emissions from Iceland’s most important volcanoes – Katla,

Öræfajökull, Bárðarbunga, Grímsvötn and Hekla (Figure 1).

Katla, Öræfajökull, Bárðarbunga, Grímsvötn and Hekla The role of Iceland’s Meteorological Office (IMO) embraces hydrology, glaciology, seismology and volcanology, including undertaking risk assessments for all natural hazards as requested by the government. Consequently, its close links with the Department of Civil and Emergency Management, responsible for the issuing of specific hazard advisories and warnings, are important. In the period 2016–18, it published a number of reports on increasing seismic activity from Katla, Öræfajökull, Bárðarbunga, Grímsvötn and Hekla.

For whatever reason (‘slow’ news days?), overseas’ print and social media particularly embraced the autumn 2018 reports regarding Katla and Bárðarbunga. Experts were interviewed and sensationalist stories published of imminent eruptions likely to ‘dwarf’ Eyjafjallajökull-style travel chaos. Given the fact that Bárðarbunga’s risk level was set to the penultimate ‘orange’, this is perhaps understandable. However, mistranslation and misquoting of expert opinion is less so. Even the normally staid Sunday Times headlined Katla’s ‘imminent eruption’, forcing a published apology in late September.

The underlying evidence of an increasing level of activity is not disputed. Despite Hekla’s greater prominence, Katla has long been recognised as Iceland’s most dangerous volcano. Its 10 km diameter caldera – erupting on average about twice per century – is located underneath the Mýrdalsjökull ice cap. It is the most active it has been in four decades, producing seismic tremors in excess of magnitude 3 and large volumes of carbon dioxide (CO

2). If a major eruption were to result, the greatest threat would be flooding by jökulhlaup (glacier bursts). For example, sandur (outwash) deposits from lahars resulting from the last confirmed eruption to break ice cover (1918) extended the southern coast by 5 km. Consequently, justification for Katla’s close geophysical monitoring and associated contingency planning is self-evident. However, the IMO has stated very clearly that actual predictions of the timing of future eruptions remains elusive: ‘there is no way of telling when it will erupt, just that it will’.

So, how unusual is this level of activity? In

July 2018, Öræfajökull (pr. Er-eyeva-yurkul) showed clear signs of unrest, with increased seismic activity and ongoing inflation following a ‘characteristic deformation pattern’. IMO reporting likened the 10 million m3 magma injection to Eyjafjallajökull’s preliminary behaviour some years before the eruption in 2010. It stressed that Öræfajökull was in a typical preparation stage before an eruption, indicating increasing geothermal activity with associated floods and gas release as a possible resulting scenario. Civil protection officials and earth scientists held public information meetings with both the local population and tour operators, remote sensing instrumentation in the area was increased and an emergency evacuation plan was prepared. In short, this is what happens in Iceland.

Bárðarbunga’s (pr. Bower-de-bunker) last ‘record-breaking’ eruption (2014–15) went on for six months. Around 2 km3 of basaltic lava and ash were released from flank fissures marginal to the ice cover, and the subglacial 700 m-deep

Iceland’s volcanoes

Tim Bayliss examines how the eruptive history, contemporary activity and predictive uncertainties of Iceland’s volcanoes maintain a small island nation’s global significance.

Figure 1 Significant Icelandic volcanoes

Bárðarbunga – lava fountaining and fissure flow, September 2014

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caldera grew significantly. However, within months of the eruption starting (at the end of August) the IMO’s highest ‘red’ alert for aviation was downgraded, despite sulphur dioxide (gas) contamination remaining in the area.

Magnitude 3 seismic tremors in autumn 2018 revealed two ascending clusters of magma. However, at the time of writing these have not reached the surface and so there has not been another eruption. It remains uncertain whether such an event would be gentle or violent. Once again a fundamental reality of volcanic prediction science is being faced: only a few hours notice is likely, which means that contingency planning for all probable scenarios must progress.

In this instance, both magma clusters are away from the heart of the main volcano. This makes it less likely that an eruption will produce the fine ash that causes air travel disruption. However, melting of the overlying Vatnajökull glacier ice (calculated as 14 times the volume of magma) would cause depression of the ice surface, adding significant quantities of water to rivers, and so increase flood risk downstream. Worst-case scenarios include the possibility that volcanic activity develops further to the southwest, where less remote dormant volcanoes (beyond Grímsvötn) and major fissures (up to 100 km long) could reawaken: ‘At some time in the future there will be a major fissure eruption to the southwest of Bárðarbunga – we just don’t know when’. This region produces much of Iceland’s hydroelectric energy, and so yet more contingency plans are in place for such an eventuality.

Grímsvötn (pr. Grims-votten) is so close to Bárðarbunga that it is likely to be fuelled by the

same source of magma. Its 2011 eruption sent a huge plume of ash into the skies, grounding several flights. Consequently, the steadily rising seismic activity reported in 2018 has been monitored closely.

However, it is Hekla that is the most prominent, best-known active volcano on Iceland. Infamously referred to in the Middle Ages as the ‘Gateway to Hell’, this 1491 m high stratovolcano has a long history of frequent eruptions associated with explosive lava fountaining, extensive basaltic andesite lava flows and fluorine-rich tephra (which is very hazardous to grazing animals). The most recent eruption, in 2000, produced an ash cloud 6 km high! In June 2016, an Icelandic geophysicist advised tourists to stop visiting this ‘dangerous’ volcano (over which 20–30 aeroplanes fly every day): ‘We could be looking at a major disaster when the next eruption begins if we are not careful’.

ConclusionIceland has more volcanic activity than anywhere else on earth. Indeed, it may be a small country, with a volcanic activity zone even smaller, but one-third of all lava flows globally are Icelandic and a volcano erupts there, on average, every four years. For this reason, Iceland commands extraordinary media interest (resulting, somewhat perversely, in an additional tourist dividend). In short, Iceland is exciting to the outside world. Media bandwagons are perhaps inevitable and the future is certain to bring new stories – whether scaremongering or hard, factual reporting of a new, major volcanic event. Meanwhile this resilient, organised and pragmatic nation will continue to learn, to monitor and to prepare. TE

RESPONSEAssimilation1 Why is Iceland called the ‘land of fire and ice’?

2 Study Figure 1. With reference to plate tectonics, comment on the

distribution of the ‘significant’ Icelandic volcanoes identified.

3 Comment on the significance of the 1973 eruption of Eldfell on Heimaey.

4 To what extent are summit inflation, increased seismic activity and gas

emissions helpful predictors of volcanic eruptions?

5 Outline the reasons why contemporary contingency planning in

southwest Iceland is so important.

Evaluation1 Referring to named events in the text and drawing on your

understanding of volcanic processes, prediction, impacts and

responses, suggest reasons why Icelandic volcanism commands such

media interest.

ANSWER PLAN

• Outline, briefly, the context of the question (Iceland’s volcanic

significance globally and contemporary preliminary activity).

• For each of volcanic processes, prediction, impacts and responses,

systematically outline recent factual Icelandic information and

the nature of the media response. (Keep generic comments to a

minimum.)

• Ensure that specific, located references are made in all

exemplification.

• Your conclusion should refer back to the question. (You may want to

include reference to Iceland’s established media profile, increasing

tourism, and even wider contemporary trends in news reporting.)

2 Suggest reasons why the aviation threat alert relating to Bárðarbunga’s

last ‘record-breaking’ eruption was so quickly downgraded.

3 Revise and outline your knowledge of methods and instruments used

in monitoring volcanoes. Why is remote sensing on Katla, Öræfajökull,

Bárðarbunga, Grímsvötn and Hekla both necessary and important?

4 ‘The world’s volcanoes combined emit less than 1% of CO2 emissions

from human activities.’ Comment on the significance of this statement in

relation to Iceland and contemporary climate change.

5 Critically evaluate the article’s conclusion.

Extension1 Contemporary, brief overviews of the Surtsey story can be found at:

https://earthsky.org/earth/surtsey-and-the-birth-of-new-islands

www.surtsey.is/pp_ens/gen_3.htm

2 The admirably ’joined-up’ nature of Iceland’s pragmatic approach to

contingency planning and the three phases following a hazard event

(relief, rehabilitation and reconstruction) can be found at:

www.almannavarnir.is/english/about-the-department-of-civil-

protection-and-emergency-management/

REVIEWKey points• Iceland has more volcanic activity than anywhere

else on earth: a volcano erupts there, on

average, every four years.

• The eruption of Eyjafjallajökull (2010) had local,

national, regional and global impacts. Cancelled

flights stranded 10 million people – at a cost to

airlines of $1.7 billion.

• Iceland’s Meteorological Office (IMO) has an

extensive role covering meteorology, climatology,

hydrology, glaciology, seismology, volcanology

and risk assessment preparation, and it

advises the Department of Civil and Emergency

Management.

• Since 2016 there have been IMO reports of

increased seismic activity and emissions from

Iceland’s most important volcanoes: Katla,

Öræfajökull, Bárðarbunga, Grímsvötn and

Hekla.

• In all instances, a fundamental reality of volcanic

prediction science is demonstrated: future

eruptions will undoubtedly happen, only a few

hours notice of any one event is likely, and

contingency planning for all likely scenarios must

progress.

• Iceland’s volcanism commands extraordinary

media interest, but there is not always balanced,

measured reporting.

Pause for thought• Any hazard event presents opportunities to learn

lessons. Review the local, national, regional and

global impacts of Eyjafjallajökull (2010) in the

light of both the ‘ash in the sky so you don’t

fly’ flight rules (which prevailed in 2010) and

contemporary understanding that computer

modelling at the time overestimated (slightly) the

concentration of ash in the sky.

• In an era of burgeoning social media and so-

called ‘fake news’, how should contemporary

reporting of volcanic activity in Iceland be

assessed?

ContextThis article broadly examines the possible future

risk from volcanoes in Iceland. There are, however,

interesting overlapping issues including those

relating to climate change and isostacy.

Hekla, near Hvolsvöllur, southern Iceland

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