Global Hazards Definitions

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Context Hazard

Widespread (global) threat due to environmental factors such as climate change.

Geophysical Hazard

A hazard formed by tectonic/geological processes (earthquakes, volcanoes and tsunamis),

Hazard

A perceived natural event which has the potential to threaten both life and property.

Hydro-meteorological Hazard

A hazard formed by hydrological (floods) and atmospheric (storms and droughts) processes.

Vulnerability

A high risk combined with an inability of individuals and communities to cope.

Disaster

A hazard becoming a reality in an event that causes deaths and damage to goods/property and the environment.

Risk

The probability of a hazard event occurring and creating loss of lives and livelihoods.

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Albedo

How much solar radiation a surface reflects.

Climate Change

Any long-term trend or shift in climate (average over 30 years) detected by a sustained shift in the average value for any climatic element (e.g. rainfall, drought, storminess).

Enhanced Greenhouse Effect

This occurs when the levels of greenhouse gases in the atmosphere increase owing to human activity.

Fossil Fuels

Energy sources that are rich in carbon and which release carbon dioxide when burnt (e.g. coal).

Global Warming

A recently measured rise in the average surface temperature of the planet.

Greenhouse Effect

The warming of the Earth's atmosphere due to the trapping of head that would otherwise be radiated back into space - it enables the survival of life on Earth.

Tipping Point

The point at which a system switches from one state to another.

Feedback Mechanism

Where the output of a system acts to amplify (positive) or reduce (negative) further output (e.g. the melting of Arctic permafrost leads to the release of trapped methane which leads to further global warming).