What you'll learn
How and why climate has changed over time.
Causes
- Natural: variations in solar output, orbital (Milankovitch) cycles and volcanic activity.
- Human: burning fossil fuels raises greenhouse gases (mainly CO₂), enhancing the greenhouse effect.
Evidence
- Ice cores, tree rings and historical records show past change.
Effects
- Rising sea levels, changing weather patterns and threats to ecosystems.
Managing climate change
- Mitigation reduces causes (renewables, efficiency); adaptation copes with effects (flood defences, drought-resistant crops).
Exam tips
- Clearly separate natural from human causes.
- Know the difference between mitigation and adaptation with examples.
Common mistakes
- Confusing the greenhouse effect with the ozone hole.
- Treating mitigation and adaptation as the same thing.