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Ocean current

Warm water comes from the equator

A gyre is a circular motion due to the surface winds.

It moves north to south

The current has an impact on the up because the north Atlantic outfit and extension the gulf scream come from the Caribbean and keeps the UK warm.

CLIMATE CHANGE: describes average weather conditions over longer periods and over large areas. Describes average weather conditions over longer periods and over large areas.

WEATHER: DAY TO DAY CONDITION OF THE ATMOSPHERE.

Drought: a prolonged period of low or no rainfall

ARIDITY: Having little or no rainfall

CLIMATE CHANGE THROUGH THE QUARTERLY PERIOD

Glacial periods-cold period

Interglacial-warm period

Temperature increases at the same time as co2 concentration increases

Physical causes of climate change

Changes in the sun energy

Changes in the earth orbit

Volcanic eruption

Photosynthesis

Impact of climate change

European countries could face less summer

Forecast changes

Glacier Melting

Factor affecting the UK climate

Latitude or distance from the quarter

Attitude or height above the sea level

Distance from the sea

Ocean Currents

Prevailing wind

Formation of hurricane

When this warm and wet air rises, it condenses to form towering clouds, heavy rainfall. It also creates a low-pressure zone near the surface of the water.

Rising warm air causes the pressure to decrease at higher altitudes. Warm air is under a higher pressure than cold air, so moves towards the ‘space’ occupied by the colder, lower pressure, air. So the low pressure ‘sucks in’ air from the warm surroundings, which then also rises. A continuous flow of warm and wet air continues to create clouds and rain.

Air that surrounds the low-pressure zone at the centre flows in a spiral at very high speeds - anti-clockwise in the northern hemisphere - at speeds of around 120 km/h (75 mph).

Air is ejected at the top of the storm – which can be 15km high – and falls to the outside of the storm, out and over the top, away from the eye of the storm. As this happens, it reduces the mass of air over the ‘eye of the storm’ - causing the wind speed to increase further. Some ejected air also cools and dries, and sinks through the eye of the storm, adding to the low pressure at the centre.

The faster the winds blow, the lower the air pressure in the centre, and so the cycle continues. The hurricane grows stronger and stronger.

Seen from above, hurricanes are huge circular bodies of thick cloud around 450 km (300 miles) wide. The cloud brings heavy rain, thunder and lightning.

In the centre is the eye of the hurricane, about 45 km across (30 miles) across. Often there will be no clouds in the eye. Seen from below it will seem calmer, with a circle of blue sky above. The eye is formed because this is the only part of the hurricane where cold air is descending.

In the northern hemisphere, the prevailing easterly tropical winds tend to steer hurricanes toward land - although their course is unpredictable. As hurricanes move inshore, their power gradually reduces because their energy comes from sucking up moist sea air.

DROUGHT

Example drought: people dying from dehydration, animal dying from dehydration, hard to find water, ocean, lake and well have been dried up