Download Impacts of volcanic activity

Impacts of volcanic activity
Key knowledge: examine the impact of change on
natural environments and human activity.
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Benefits for human activities
Fertile soil: Volcanic soils break
down to produce some of the
most fertile soil on Earth, rich in
iron and magnesium. Greater crop
production leads to higher
population densities in volcanic
areas.
Places such as the African Rift Valley, Mt
Elgon in Uganda, and the slopes of
Vesuvius in Italy all have productive
soils thanks to the breaking down of
volcanic rocks and ash
Benefits for human activities
High Biodiversity : volcanic regions generally
have a greater biodiversity than non-volcanic
regions. The higher the altitude of many
volcanoes also produces orographic rainfall. As a
result, natural vegetation and crop grow quickly
and support a wide variety of animal species.
Biodiversity is the
variety of living things
Orographic rainfall is rainfall
produced by condensation
around mountains.
Benefits for human activities
Mineral deposits: most valuable metallic mineral ores
mined in the world are associated with past volcanic
processes. Minerals such as gold, silver, copper, lead
and zinc are concentrated by tectonic activity.
Benefits for human activities
Fossil fuels: coal, oil
and natural gas are
produced in geologic
basins formed by plate
tectonic processes.
Benefits for human activities
Geothermal energy: steam from active volcanic regions
and underground rocks can be used to generate
electricity and supply hot water and heating needs. More
than 70% of Iceland’s homes are heated with geothermal
energy.
The main form of geothermal power is where bodies of water, either
above or below the earth's surface, are converted to steam by the
earth's heat. The steam is collected, and used to power a
turbogenerator just like in a regular coal fired power station.
The other form is called hot rock geothermal energy. It is where water
is pumped below the surface to areas of hot rock. The water turns to
steam, and is brought back to the surface to drive a turbogenerator.
Benefits for human activities
Tourism: Volcanic sites can also be very effective tourist
attractions. Even the less active ones that are just puffing out
steam and smoke are impressive sights and attract tourists
from around the world. Warm bathing lakes, hot springs,
bubbling mud pools and steam vents are often present
around volcanoes, drawing in tourists.
The affect of volcanic gases on global temperature
Global temperature drops.
Acid droplets absorb incoming solar
radiation and are reflected back into
space.
Sulphuric acid clouds form.
Sulphur from eruption mixes with water
vapour in atmosphere.
Reading found on pages 49-50
Questions to be completed from page 51