Learning Goals
- Compare mitigation and adaptation responses to climate change in terms of purpose and example.
- Apply unit knowledge to evaluate a real-world coastal community's response options.
- Connect the science, impacts, and action threads into one reasoned argument.
Warm Up
Compare two
Complete the table to compare mitigation and adaptation. Fill in all blank cells.
| Feature | Mitigation | Adaptation |
|---|
| Main goal | | |
| Does it reduce emissions or cope with change? | | |
| One Australian example | | |
| Why we still need it even if we do the other | | |
Your Turn
Real-world context
A low-lying coastal town in New South Wales is already seeing more frequent flooding of its waterfront streets during king tides and storm surges. Local sea level has risen and is projected to keep rising for decades because of thermal expansion and melting land ice. The council is debating its response. Some residents argue, "If we just build a higher sea wall, we don't need to worry about cutting emissions."
(a) Explain why the local sea level will keep rising for decades even if the world reaches net-zero emissions soon. Use the idea of thermal inertia in the oceans.
Apply
2 marks
(b) Classify the sea wall as mitigation or adaptation, and justify your choice. Then suggest one mitigation action the same town could also take.
Apply
3 marks
(c) Evaluate the resident's claim that "a higher sea wall means we don't need to cut emissions." Use evidence from the unit to explain why mitigation and adaptation are both needed.
Apply
3 marks
Answer Key (Teacher)
- Compare two: Main goal, Mitigation = reduce or remove greenhouse gas emissions to slow warming; Adaptation = reduce harm by adjusting to changes already happening. Reduce emissions or cope with change, Mitigation = reduces emissions; Adaptation = copes with change. Australian example, Mitigation = solar/wind farms, pumped hydro, electrification, blue-carbon wetlands (accept any); Adaptation = sea walls, managed retreat, drought-tolerant crops, water-sensitive urban design, cool burning (accept any). Why we still need it, Mitigation = limits how bad change gets because adaptation has limits and rising costs; Adaptation = needed because some warming is already locked in and cannot be avoided by cutting emissions alone.
- (a): The oceans have absorbed about 90% of the extra heat and release it only slowly, so they keep warming and expanding for decades (thermal inertia/lag). Land ice also continues to melt. Reaching net zero stops adding to warming but does not quickly reverse the heat and CO2 already stored, so sea level keeps rising. 1 mark for thermal inertia/ocean heat lag; 1 mark for linking this to continued sea-level rise.
- (b): The sea wall is adaptation (1 mark): it does not reduce emissions; it helps the town cope with rising seas already locked in (1 mark justification). A suitable mitigation action: install rooftop or community solar, switch the council fleet to electric vehicles, support a local renewable energy project, or restore blue-carbon wetlands (1 mark for any valid mitigation).
- (c): The claim is misleading. A sea wall (adaptation) only manages local symptoms and has limits and rising costs as seas keep rising; it does nothing about the cause. Without mitigation, emissions and warming keep growing, so impacts such as higher seas, coral reef loss and ocean acidification continue and some cannot be adapted around. Therefore both are needed together: mitigation limits how bad change gets, adaptation copes with change already locked in. Award up to 3 marks: identifies claim as flawed; uses evidence (e.g. adaptation limits, continued warming, irreversible impacts); concludes both are needed.
Wrap Up
In one sentence, what was the main idea of this lesson?