Montserrat Eruption Flashcards
Facts
- Eruption began on 18th July 1995 when clouds of ash and steam erupted
- Volcano is situated on the south side of the island
- Southern ⅔ of the island is now uninhabitable
- First eruption in 250 years
Tectonic setting:
Convergent plate margin - North American plate subducting under the Caribbean plate
-At the plate boundary water is forced out - due to the high pressure rock melts and the mixture of molten rock and pressurised water forces it upwards into the vent
Sequence of events:
- 1992/1994 - Earthquakes first detected
- 1995 - Eruption of ash/steam, 5000 people are evacuated and as the dome expands Plymouth is evacuated (December)
- 1996 - First pyroclastic flow down the Tar River valley and the whole of the south side ofthe island is evacuated
- 1997 (June) - pyroclastic flow down the NE slope of the volcano which kills 19 people who went unto the danger zone - 9000m high ash column
- 1997 (August) - pyroclastic flow destroys Plymouth which is 3 miles from the crater - a permanent relocation of the evacuees is considered by the British government and the exclusion zone is expanded -residents advised to stay under shelter, wear helmets and masks outdoors
- 1997 (September) - officials advise that all residents move as far north as possible, 5000 people live in shelters
- 1997 (October) - eruptions every 9 hours
- 1997 (November) - Dome collapses causing a large eruption
- 1997 (December) - Boxing Day eruption - pyroclastic flow down the white river valley - ash column to 36000 ft
- 1999 (July) - dome collapses causing a large eruption - cloud reaches 35000 ft - people are out of danger providing they are not in the exclusion zone
Primary Impacts:
- 5000 people living in temporary shelters
- Jobs/ communities/ schools disrupted
- Plymouth contained the main services: hospitals, schools, banks, government buildings
- Shortage of housing
- 19 people killed
- Plymouth was buried in 12m of mud
- 7000 people displaced - went to the north of the island, other caribbean islands or the UK
- 70% rise in rent fees
- Main port was closed - trade could now only come from the airport on the edge of the exclusion zone
- Skills shortage
- Initial fall in tourism
- Farmland destroyed
- Half of the population who left the island did not return
- ⅔ of the island was covered in ash destroying all vegetation - vegetation destroyed by acid rain
Secondary impacts:
- Respiratory problems
- Psychological problems
- Children could not go to school/ adults could not work
- Massive loss of tourism
- Unemployment rose from 7% to 50%
- Population decreased by 6823 people between 1991 and 2001 - loss of 60,3% of the population from 11000 to 4000
- Growth in tourism due to the volcano
- Flights to and from the caribbean and transatlantic flights were cancelled
- Shortage of available building land
- Forest fires from pyroclastic flows
- Flood occurred/ lahars when the valleys were blocked with ash
Management:
- Once the volcano was deemed too dangerous to live in an evacuation plan was created where two thirds of the island was in the exclusion zone
- Monitoring:-
- Seismograph to measure earthquake strengths and depths
- Titlemeters were put in place to show if the volcano was expanding due to magma rising
- GPS was used to check for ground movements
- The pH of rainwater was monitored to give an idea of gas emissions
Short Term Responses:
- Evacuation
- Abandonment of the Plymouth
- UK donated $62 million in aid and a further $113 million to assist long term development
- Fall in the economy where the private sector became reliant on UK aid
Long Term Responses:
-Aid to establish new infrastructure in the north was seriously delayed, leaving people to live as refugees for years. Montserratians who chose to emigrate were given such a small resettlement fund, they could not stay out of poverty; and because those who moved to the UK were not British citizens, they could not work.
-Exclusion zone was set up and still in place
-New roads and a new airport were built
-Services in the north of the island were expanded
$3600 was given to every person who had to move - this allowed them to move country
-Montserrat Volcano observatory (MVO) was setup to study the volcano and provide warnings of future eruptions
