* Volcanic hazards - Impacts & Responses4

What are primary impacts of an eruption?

A direct result of the eruption, e.g. people can be killed by falling tephra.

What are the secondary impacts of eruptions?

They occur as a result of the primary impacts, e.g. pyroclastic flows can melt glaciers and cause flooding.

What do volcanic eruptions have impacts on?

People and the environment

What are some social impacts of volcanic eruptions?

• People killed, and buildings and infrastructure destroyed by pyroclastic flows and fallout.

• Pyroclastic flows and lava flows can start fires that damage buildings.

• Mudflows and flooding from ice melt can cause more damage and deaths.

What can happen to ecosystems (environmental impacts)?

They can be damaged or destroyed by flows and fallout of volcanic material.

What impacts can acid rain have? (Environmental)

Can cause acidification of aquatic ecosystems, killing some plants and animals.

It also damages the leaves of trees and removes nutrients from soil, damaging forests.

What impacts can volcanic gases have? (Environmental)

They contribute to the enhanced greenhouse effect and can add to global warming.

What impacts can clouds of ash and volcanic debris have? (Environmental)

Clouds of ash and volcanic debris can reduce the amount of sunlight reaching Earth, decreasing temperatures over large areas.

What impacts can eruptions have on economies? (Economic)

Can destroy businesses, and ash clouds can prevent aircraft flying and damage crops.

This damages the economy of the region and the country.

What other economic impacts can eruptions cause?

• Damage to buildings and infrastructure can be very expensive to repair.

• Eruptions and the scenery they form can attract tourists, boosting the economy.

What political impacts can eruptions cause?

• Damage to agricultural land can cause food shortages, leading to conflict and political unrest.

• Governments may have to spend money on repairing damage to buildings and roads, rather than e.g. hospitals and schools, so countries may not develop as rapidly.

What is hazard mitigation?

Anything that is done to reduce the severity or impacts of a hazard.

Can be done through short term or long term responses to the volcanic hazard.

When do short term responses normally occur?

Immediately before, during or immediately after the hazard begins.

What do short term responses include?

Things like evacuating people from areas at risk from an eruption and providing emergency food supplies.

What are long term responses designed to do?

Reduce the impacts of future eruptions by managing the risks.

What 3 categories do long-term responses fall into?

• Prevention.

• Preparedness.

• Adaptation.

What is prevention of eruptions?

• Not possible to prevent a volcanic eruption.

• But is possible to prevent them posing a risk to people - e.g. authorities can prevent land around volcanoes from being developed.

What is preparedness about?

What happens before an eruption to minimise risk or vulnerability.

What can authorities do during preparedness?

• They can install monitoring systems to predict when an eruption might occur, and make plans for how they will evacuate people if there is an eruption.

• If eruptions are imminent, authorities can stop people entering the area around the volcano.

What can individuals do during preparedness?

They can make sure they are prepared, e.g. by finding out where their nearest emergency shelter is, or making an emergency kit containing a torch, medicine, dust masks etc.

What can communities do during preparedness?

They can set up search and rescue teams or fire response units to tackle impacts of an eruption.

What is adaptation about?

How people change their behaviour or surroundings to minimise the risks and maximise the benefits of leaving near a volcano.

Give some examples of adaptation

• Buildings can be strengthened to reduce chance of collapse if a layer of ash lands on them.

• People can capitalise on opportunities of leaving near a volcano, e.g. by farming (ash makes soil fertile) or working in the tourist industry.