Volcanic Hazards - Impacts and Responses Flashcards
What are primary and secondary impacts?
Primary impacts- direct result of the eruption e.g. people can be killed by falling tephra.
Secondary impacts- Occur due to the result of primary impacts e.g. pyroclastic flows can melt glaciers and cause floods.
How do volcanic eruptions have impacts socially, economically, environmentally, and politically?
Social:
> People are killed, and buildings and infrastructure are destroyed by pyroclastic flows and fallout.
>Pyroclastic flows and lava flows start fires that damaged buildings
> Mudflows and flooding from ice melt can cause further damage and deaths.
Economic:
> Eruptions can destroy businesses, and ash clouds can prevent aircraft and destroy crops.
>Damage to buildings and infrastructure can be very expensive to repair.
>Eruptions and the scenery they form can attract tourists, boosting the economy.
Environmental:
> Ecosystems can be damaged or destroyed by flows and the fallout of volcanic material.
> Acid rain can cause acidification of aquatic ecosystems, killing some plants and animals. It also damages the leaves of trees and removes nutrients from the soil, damaging forests.
>< Volcanic gases increased to the enhanced greenhouse effect and can add to global warming.
> Clouds of ash/volcanic debris can reduce the amount of sunlight reaching the earth, decreasing temperatures over large areas.
Political:
>Damage to agricultural land can cause food shortages, leading to conflict and political unrest.
>Government may have to spend money on repairing damage to buildings and roads, e.g. rather than schools and hospitals, so countries may not develop as rapidly.
What are pyroclastic flows?
A pyroclastic flow is a dense, fast-moving flow of solidified lava pieces, volcanic ash, and hot gases
When do short-term responses occur?
Short-term responses normally occur immediately before, during, or immediately after the hazard begins- they provide things such as evacuation and food supplies.
When do long-term responses occur?
Long-term responses are designed to reduce the impacts of future hazards after past experiences. e.g. prevention, preparedness, and adaption.
What are the 3 main long-term responses to a volcanic eruption?
Prevention:
> It’s not possible to prevent a volcanic eruption.
> However, it is possible to prevent eruptions from posing risk to people e.g. authorities can prevent land around the volcano from being developed further.
Preparedness:
> Authorities can install monitoring systems to predict when an eruption might occur, and make plans on how they will evacuate people.
>Authorities can stop people from entering the area if an eruption is likely.
>Individuals can make sure they are prepared by finding the nearest emergency shelter or making an emergency kit containing a torch, medicine, and dust masks.
>Communities can set up search and rescue teams or fire response units to tackle the impacts of the eruption.
Adaption:
> Adaptions are about how people change their behavior and surroundings to minimize the risk of a volcano.
> Buildings can be strengthened to reduce the chance of collapse if a layer of ash lands on them.
> People can capitalize on the opportunities of living near a volcano e.g. by farming (volcanic ash makes the soil very fertile) or by working in the tourist industry.
