forms of volcanic hazard

Question 1

flooding

Answer 1

caused by melting icecaps/glaciers - rivers can increase discharge by 1000x

Question 2

lahars (mudflow)

Answer 2

volcanic ash and water - sets hard like concrete, travels at 40m/s for long distances up to 300km
tropical storms - hurricanes and monsoon rain - make it worse

Question 3

mass movement

Answer 3

landslides, rockfalls - triggered by eruption or seismic activity

Question 4

lava (basaltic)

Answer 4

travels slowly 1-2km/hr, temp 1000 degrees

Question 5

gas

Answer 5

Co2, sulphur dioxide, carbon monoxide, hydrogen chloride
acid rain created - damage to vegetation, pollute water supplies, asphyxiation/suffocation of people/livestock
Aerosols - reflect and scatter incoming sunlight, global cooling

Question 6

pyroclastic flow

Answer 6

mixture of debris, gas, ash, 900 degrees, fast - 200km/hr, caused by eruption column collapsing

Question 7

tephra

Answer 7

ash (<2mm)
volcanic bombs (>5cm) - small fragments of rock created by shattering of magma
- breathing problems, small covering of ash (5cm) enough to cause roofs to collapse, heat can cause burns, aeroplanes