Eyjafjallajökull and Montserrat (Case study volcanoes)

Location and background of Eyjafjallajökull

• Erupted in March 2010 and intensified in April, located on spreading ridge in Iceland. Quite a small population with a population density of 3 people per m³

Timeline of events

• Erupted last time in 1821-1823. Increased EQ activity and swelling between 1990s up to early 2010s suggesting movement of magma

• Initially a fissure eruption on 20th March. Eruption shifted beneath Eyjafjallajökull ice cap, melting ice lots of steam. 14th April

• Between 15-20th April continued erupting in bursts ash plumes up to 5-8km high. Ash fall and flooding due to glacial melting

• Late May activity declined and ended by June

Nature of Eyjafjallajökull eruption

It was a composite volcano which was covered by Eyjafjallajökull ice caps. Explosive eruptions when magma meets ice. Ash clouds, lava flows and flooding.

Caused by magma movement causing gas pressure build up and interactions of magma and ice causing steam explosions.

VEI4 but ash clouds produced caused massive effects. Ash plumes up to 9km high.

Primary impacts

• Ash cloud ejection 9km high, flooding, ash fall and air pollution.

• New land formed by lava flow cooling and solidifying creating new rock.

Secondary impacts

• Over 100,000 flights cancelled

• Global airlines lost around $1.7b USD

• Kenya lost around 150,000 million stems affecting their economy

• Farming disrupted as feed was contaminated, food shortages

Immediate responses

• Evacuation of 800 residents

• Roads closed and bridges protected

• Flights grounded across Europe

Long term responses

• Drills and public education

• Rebuilt and reinforced flood defences

• Improved global volcanic monitoring networks

How did certain factors mitigate impacts of Eyjafjallajökull

• Eyjafjallajökull located in a HIC with strong monitoring and prediction systems which helped evacuation efforts to reduce risk of death and injury

• Government had resources to respond and recover rapidly

• Strong infrastructure and healthcare reduced long-term impacts

Location and background of Montserrat

Located in the Caribbean and was an island near the Soufriere hills. Had population of around 12,000 before eruption.

When did the Soufriere hills volcano erupt

It became active in 1995 with main eruptions occurring in 1997.

What were the primary effects of the eruption

• 19 deaths due to pyroclastic flows in June 1997

• Capital Plymouth and farmland buried in ash

• Over 7,000 residents displaced

• Airport and dock destroyed

What were the secondary effects of the eruption

• Population more than halved down to 5,000 from 12,000 most went to UK

• Tourism industry collapsed

• Unemployment rose sharply

• Psychological trauma

• Pyroclastic flows resulted in forest fires

What were the immediate/short term responses

• Evacuation of 7,000 residents

• Emergency operation centre set up

• Temporary shelters set up in the North

• Aid from the UK

What were the long term responses

• Air and sea links re-established

• UK gov spent £100 million in assisting migration and restoration

• Permanent exclusion zone set up

• Improved monitoring and warning system

• 40km² of 100km² island considered safe

Was there any preparation or mitigation

Not really before 1995, not any evacuation plans and limited monitoring most mitigation introduced after eruption, few hazard maps

How did certain factors influence mitigation impacts of Montserrat

• Recovery depended heavily on aid from the UK

• Small island economy so had less resources to respond to hazard

• Destroyed capital meant main port removed and many businesses leading to economic decline and mass emigration making responding to eruption much harder