Raffles Junior College
JC 1 Physical Geography
Volcanoes
Supplementary Pointers
Effects of Volcanic Eruptions

Tsunami, landslide, earthquakes, torrential rains

Extreme weather conditions (e.g. snow during summer in New York and global cooling after
eruption of Mount Tambora, Indonesia)

Death and injuries

Homes destroyedburied by pyroclastic flows and lahars

Damage to infrastructure (e.g. airports
damaged/destroyed)difficult for aid to arrive

Destruction and loss of agriculturelack of foodinflationwidespread famine

Damage to the Economy (commercial and industrial operations halted)

Spread of diseases (e.g. cholera)epidemics

Education disrupted

Ozone depletion following release of huge amounts of sulphur dioxide

Water supply contaminated with ash and acid rain
closed,
roads
and
communications
Management of Volcanic Hazards

Prediction (e.g. Eruption of Mt. Pinatubo in Philippines was a successful prediction which
saved many lives)
o
Measurement
of
elevation
of
slopes
of
volcanoes
(e.g.
Bulges/Swellings/Deformations in the surface may give warning that magma is
building up and the volcano is about to erupt).
o
Use of seismometers and seismographs. Frequency of tremors generated may give
indicators of volcanic activity. Tiltmeters and extensometers important too.
o
Analysis of gas content using a spectrometer can help to predict volcanic eruptions
(increasing amount of sulphur dioxide indicates rising magma)
o
Constant monitoring of the volcano’s temperature
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

o
Drawing up of a volcanic hazard map
o
Rainfall monitoring
Mitigation
o
Warning/alert systems
o
Train people in evacuation drills (public education)to get people to move faster
o
Temporary town/infrastructure build in the case of an emergency
Human Response
o
Search and rescue
o
Ordered closure of areas surrounding the volcano
o
Clean upash removal
o
Mental health programs to assist people suffering from stress and emotional
problems
o
Setting up of a volcanic monument to preserve the damaged area for studies to take
place
o
Government giving tax relief to victims
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