Hazardous Earth

Atmospheric circulation

The movement of air within the Polar, Ferrel and Hadley Cells controlled by radiation from the sun

Asthenosphere

The upper layer of Earth’s mantle below the lithosphere

Conservative boundary

Convection currents cause tectonic plates to slide past each other e.g. Haiti.

Convergent plate boundary

Where two plates are moving towards each other, resulting in the oceanic plate subducting e.g. Japan

Divergent plate boundary

Where two plates are moving apart e.g. Iceland

Enhanced greenhouse effect

The trapping of heat radiation around the Earth by excess greenhouse gases produced through human activity.

Explosivity

A measure of the relative explosiveness of volcanic eruptions varying due to formation on convergent or divergent boundaries.

Greenhouse

gases

Human activities such as energy, industry, transport and farming that produce greenhouse gases e.g. carbon dioxide and methane.

High pressure

The ‘weight’ of sinking air exerts more pressure on the ground and an area of high pressure is formed causing areas to become arid.

Lithosphere

Includes both the crust and the top layer of the upper mantle

Low pressure

The warmth of the Earth’s surface causes air to rise, exerting less pressure on the ground forming low pressure causing rainfall.

Natural climate change

Natural changes to Earth’s climate caused by Milankovitch cycles, solar variation, volcanism and surface impact.

Past climate change

Points in Earth’s history that have been comparatively warmer and significantly colder owing to natural causes.

Satellite technology

Allows huge areas of ocean to be monitored for the distinct tropical storm cloud formations.

Short-term relief

Immediate support that includes rescuing people, providing medical aid, and restoring water and electricity.

Storm surges

A tropical cyclone creates a large area of low pressure, which allows the level of the sea to rise.

Tropical cyclones

Large-scale, rotating storms that form over oceans (26.5°C) in tropical areas. They are alsoknown as hurricanes and typhoons.

Warning strategies

Forecasting, monitoring and prediction that allows advance warnings for preparation and evacuation.