Weather Hazards

- Paper 1 ( Challenges of Natural Hazards)

Economic impact

The effect of an event on the wealth of an area or community.

Environmental impact

The effect of an event on the landscape and ecology of the surrounding area.

Extreme weather

This is when a weather event is significantly different from the average or usual weather pattern, and is especially severe or unseasonal. This may take place over one day or a period of time. A severe snow blizzard or heat wave are two examples of extreme weather in the UK.

Global atmospheric circulation

The worldwide system of winds, which transports heat from tropical to polar latitudes. In each hemisphere, air also circulates through the entire depth of the troposphere which extends up to 15 km.

Immediate responses

The reaction of people as the disaster happens and in the immediate aftermath.

Long-term responses

Later reactions that occur in the weeks, months and years after the event.

Management strategies

Techniques of controlling, responding to, or dealing with an event.

Monitoring

Recording physical changes, such as tracking a tropical storm by satellite, to help forecast when and where a natural hazard might strike.

Planning

Actions taken to enable communities to respond to, and recover from, natural disasters, through measures such as emergency evacuation plans, information management, communications and warning systems.

Prediction

Attempts to forecast when and where a natural hazard will strike, based on current knowledge. This can be done to some extent for tropical storms (and volcanic eruptions, but less reliably for earthquakes).

Primary effects

The initial impact of a natural event on people and property, caused directly by it, for instance buildings being partially or wholly destroyed by a tropical storm.

Protection

Actions taken before a hazard strikes to reduce its impact, such as educating people or improving building design.

Secondary effects

The after-effects that occur as indirect impacts of a natural event, sometimes on a longer timescale, for instance impact on access to potable water can lead to spread of disease.

Social impact

The effect of an event on the lives of people or community.

Tropical storm (hurricane, cyclone, typhoon)

An area of low pressure with winds moving in a spiral around the calm central point called the eye of the storm. Winds are powerful and rainfall is heavy.

Adaptation

Actions taken to adjust to natural events such as climate change, to reduce potential damage, limit the impacts, take advantage of opportunities, or cope with the consequences.

Climate change

A long-term change in the earth's climate, especially a change due to an increase in the average atmospheric temperature.

Mitigation

Action taken to reduce or eliminate the long-term risk to human life and property from natural hazards, such as building earthquake-proof buildings or making international agreements about carbon reduction targets.

Orbital changes

Changes in the pathway of the Earth around the Sun.

Quaternary period

The period of geological time from about 2.6 million years ago to the present. It is characterized by the appearance and development of humans and includes the Pleistocene and Holocene Epochs.

Solar energy

Drives the Earth's atmospheric circulation

Atmosphere

A mixture of gases that surrounds the Earth

Atmospheric circulation

This process redistributes heat towards the poles and gives the broad patterns of air movement

Low Pressure

is where warm air rises usually bringing wet, stormy weather.

High Pressure

is where air sinks giving dryer, calmer conditions

Hadley cell

The cell that drives air around tropical regions

Ferrel Cell

The cell that moves air from 30 degrees to 60 degrees in the mid latitudes

Polar Cell

Weak circulation cell that occurs between 60 and 90 degrees latitude.

Trade winds

steady winds in tropical latitudes that blow toward the equator from the north and south

Prevailing westerlies

winds that blow west to east between 30 and 60 degrees in the northern and southern hemispheres

Deserts

are ceated where air sinks on the model

Coriolis Effect

The effect of the Earths rotation on wind movements

Cyclone

Hurricane

Typhoon

A tropical cyclone that hits Oceania or Madagascar

A tropical cyclone that hits the USA, Latin America or the caribbean

A tropical cyclone that hits India, Japan or the Philippines

Drought

Hydrological drought

Meteorological Drought

A polonged dry period in the natural climate cycle that can occur anywhere in the world

When reduced precipitation impacts water supply. There is a decrease in streamflow, soil moisture, reservoir, lake and groundwater levels

When the amount of precipitation received in an area is below average

Eccentricity

A measure of how much the Earths orbit around the sun changes from a circular shape to an eclipse

Eye

eye wall

• An are of a tropical cyclone with extremely low pressure and calm coditions

• An are of a tropical yclone with themost intense, powerful winds and torrential rain

Intertropical convergence zone

An are surrounding the equator where global winds converge, causing an area of low pressure with rainy conditions

Milankovitch Cycles

The cyclical variations in the Earths orbit around the sun. Includes : Eccentricity, Obliquity(Tilt) and precession (wobble of Earths axis)

Obliquity

Precession

The tilt of the Earths axis, which changes from 21.5 and 24.5

The ‘wobble’ of the Earths axis

Ocean currents

The predictable, continous ciculation of ocean water which transfers heat around the globe

Pressure belt

A region of the Earth which is generally under the same pressure

Storm surge

When a tropical cyclone pushes a large amount of sea water onto the shore, causing a rise in sea level