Different areas of the earth receive different amounts of solar radiation. There is a surplus at the equator and a deficit at the poles. Three circulation cells in each hemisphere redistribute this heat energy.

At the Equator, warm air rises causing low pressure. The air current divides, cools and moves north and south to form the Hadley cells. The cooled air sinks at 30° north and south, causing high pressure.

Some cool air goes back to the Equator as trade winds. The rest travels to the Poles, forming the lower part of the Ferrel cells

At 60° north and south, the warmer air of the Ferrel cells meets colder polar air. The warmer air rises to form Polar cells, which travels to the poles and sinks, causing high pressure.

Ocean currents also transfer heat energy from areas of surplus to areas of deficit. Both wind-driven surface currents and deeper ocean currents move warm water to the poles and cool water to the poles

Important ocean currents include the Gulf Stream and the North Atlantic Drift (look at the book or something)

Denser and colder water sinks, and warmer water replaces it, causing ocean currents

Long-term changes to the Earth's orbit and position, affecting the amount of solar radiation the Earth receives, affecting climate.

Eccentricity cycle: the Earth's orbit changes approximately every 100,000 years. Circular orbit = cooler periods; elliptical orbit = warmer

Precession cycle: the Earth "wobbles" on its axis every 24,000 years, changing the direction the axis is facing. This affects the differences between seasons

Axial tilt cycle: every 40,000 years the tilt of the Earth's axis varies. Greater angle = more extreme conditions (hotter summer cooler winter)

Ice cores trap volcanic ash, microbes and air bubbles. It reveals information on climate when it formed

Preserved pollen shows which plants grew at what time, indicating the climate at the time

Growth rings on trees: width of the rings; warmer climate = wider rings and vice versa

Solar radiation levels just naturally vary. Lower radiation increase chance of glacial period, higher radiation causes inter-glacial period

Volcanic eruptions eject ash and dust into the atmosphere, acting like a blanket and blocking out solar radiation causing temperatures to fall

The Quaternary period (the last 2.6m years), where there have been more than 60 cold periods with ice advances lasting around 100,000 years and warmer inter-glacial periods lasting about 15,000 years

Recently, (in the last 250 years), the Earth's temperature has risen significantly compared to before, by about 5°C compared to the last ice age

Medieval Warm Period (950-1100): increased solar radiation > higher temperatures > better crop yield and growing population

Little Ice Age (1600-1685): Increased volcanic activity > decreased solar radiation > temperatures low enough to freeze the Thames

NE: cold winters, cool summers
SE: cold winters, warm summers
NW: mild winters, cool summers
SW: mild winters, warm summers

Maritime influence: UK is surrounded by sea, so most of its air is moist, causing rainfall all year

Prevailing wind: coming from the south west, over the Atlantic, carrying more moisture leading to more rainfall

North Atlantic Drift: Ocean current brings warm water to UK, making the climate milder than expected for its latitude

Atmospheric circulation: the UK is near the boundary between northern Ferrel and Polar cells. Warm air from the south and cool air from the north meet, causing unsettled weather

Altitude: different areas in the UK vary due to altitude. (The higher an area is, the cooler and wetter it is).

The boundary between cold and warm air is known as the Polar front