3.1.1.1 Natural Hazards

Define a natural hazard

A natural hazard is a natural process or event that has the potential to cause death, injury, or disruption to humans, or destroy property and possessions.

By what do we categorise natural hazards?

By their physical causes

What are the main categories of natural hazards? Give some examples of hazards for each category.

Geological

• These are caused by land and tectonic processes, primarily involving the Earth's crust and mantle.
  E.g. Earthquakes, volcanic eruptions

Hydrological

• These are caused by changes in the water cycle
  E.g. Flooding, droughts, landslides, tsunamis

Atmospheric/ Meteorological

• These are caused by atmospheric processes, weather etc.
  E.g. Hurricanes, tornados, rain, lightning

Note, these can all overlap (there is also biological, so pests disease etc.)

What is hazard risk?

The chance or probability of being affected by a natural event

List the main factors affecting hazard risk

Urbanisation/ population
Poverty
Farming
Climate change
Magnitude + frequency
Prediction

How does urbanisation affect hazard risk?

Densely populated urban areas (e.g., Tokyo or LA) have more people and infrastructure in one place, meaning a single event causes more death and damage.

How does poverty affect hazard risk? (think about on an individual level and a more countrywide level)

Individual level:

• Impoverished people (LICs) may be forced to live in high-risk areas (e.g., steep slopes or floodplains) and lack the money for "earthquake-proof" buildings. They also cannot afford to move.

Countrywide level:

• LICs often have poor investment into protection and management of hazards can often lead to more severe impacts

• Don't have money to spare

How does farming affect hazard risk?

People often settle in hazardous areas like floodplains or near volcanoes because the soil is extremely fertile (want to farm, want money etc.), putting them at higher risk.

How does climate change affect hazard risk?

Rising global temperatures lead to more energy in the atmosphere, increasing the frequency and intensity of storms, floods, and droughts.

How does the magnitude and frequency of a natural event affect hazard risk?

How often a hazard event occurs as well as the size and strength of the event

• If a hazard happens rarely, people may be less prepared for it.

• A magnitude 9.0 earthquake poses a significantly higher risk than a 3.0.

How does prediction affect hazard risk?

Some hazards such as earthquakes are impossible to predict and so people have no warning

HICs generally have a higher hazard risk than LICs

TRUE OR FALSE

explain why

False

High-Income Countries (HICs):
Usually have lower hazard risk because they can afford better prediction technology, stronger buildings (mitigation), and efficient emergency services.
BETTER CAPACITY TO COPE

Low-Income Countries (LICs):
Often have higher hazard risk due to a lack of resources to prepare for or recover from an event.
WORSE CAPACITY TO COPE