causes

• sunspots- solar storms known as sunspots emit flares of heat which radiate towards earth. This temporally increases the temperature of the earth - Example: 17th century Britain experienced a period of cooling for around 70 years as there was little sunspots, this is known as the little ice age
• Sunspot timing- every 11 years
• Orbital forcing (stretch, tilt, wobble) - over thousands of years the earths tilt changes, its orbit (stretch) changes and wobbles on its axis. This can cause the earth to cool or warm -Example: When the earth tilts more on its axis the climate warms, this is thought to explain why the ice age ended
• Orbital forcing (stretch, tilt, wobble) timing- stretch every 100,000 years, tilt every 41,000 years, wobble every 26,000 years.
• Volcanic eruptions -ash and gas are ejected into the atmosphere during an eruption. these particles reflect heat energy from the sun, preventing it from reaching earth, temporally cooling the planet - Example: Located in the phillipines Mount Pinatubo erupted in 1991 sending 30 million tonnes of sulphur dixoide into the atmosphere and caused 3 years global cooling.
• Volcanic eruption timings- a few months/ years
• Transport- the burning of fossil fuels such as petrol for transport, release tones of Co2 into the atmosphere . Co2 can spend up to 200 years in earths atmosphere
• Farming- Due to the increasing population and the high demand for meat and dairy products, farmers must increase amount of cows. When cows belch they release methane which is a greenhouse gas 25-30% more potent than Co2 and therefore trapping more heat. Methane can stay in earths atmosphere up to 12 years.
• CFCs- Human made chemical compounds were used in aerosols, fridges and polystyrene. They were banned in 1987 to prevent any further damage to the o-zone layer. CFCs can stay in the atmosphere for up to 100 years
• Human causes- Transport , farming , CFCs
• Physical causes- sunspots , orbital forcing (stretch, wobble,tilt,), volanic eruptions