Case Studies:

Climate change is the long-term change in average global temperatures and weather patterns, mainly caused by human activities that increase greenhouse gases in the atmosphere.

the greenhouse effect

The greenhouse effect is the process by which heat from the Sun is trapped in Earth’s atmosphere, keeping the planet warm enough to support life.

• Solar radiation from the Sun reaches Earth’s surface.
• The Earth absorbs this energy and re-radiates it as heat.
• Greenhouse gases in the atmosphere trap some of this heat.
• This prevents too much heat from escaping into space.

Enhanced Greenhouse Effect

Human activities increase the amount of greenhouse gases.

• More heat is trapped than normal.
• This causes global warming, leading to climate change.

greenhouses gases

• Carbon dioxide (CO₂): Released by burning fossil fuels and deforestation. It is the main cause of human-induced climate change.
• Methane (CH₄): Produced by livestock farming, landfill sites, and rice paddies. It traps much more heat than CO₂.
• Nitrous oxide (N₂O): Released by fertilisers and industrial processes.
• Water vapour: Increases as temperatures rise, reinforcing warming.

causes

Human Causes

• Burning fossil fuels (coal, oil, gas) for energy and transport releases carbon dioxide (CO₂).
• Deforestation reduces the number of trees absorbing CO₂.
• Agriculture releases methane (CH₄) from livestock.
• Industry produces greenhouse gases during manufacturing.

Natural Causes

• Volcanic eruptions release gases and ash.
• Changes in Earth’s orbit affect how much solar energy reaches Earth.