The concept of 'tipping points' in climate science refers to critical thresholds that, once crossed, lead to significant and often irreversible changes in the Earth's systems. For instance, the melting of the Greenland ice sheet is not a gradual process but could accelerate dramatically once a certain temperature is sustained. Similarly, the Amazon rainforest, which acts as a major carbon sink, may undergo a dieback process if deforestation and drought exceed a certain level, converting it from a carbon absorber to a carbon emitter. These thresholds are characterized by nonlinear responses, meaning that small perturbations can trigger disproportionately large effects. Understanding tipping points is crucial for policymakers, as they imply that mitigation efforts must be proactive rather than reactive, because waiting for visible signs of damage may leave insufficient time to avert catastrophic outcomes. However, the exact location of these thresholds remains uncertain, complicating decisions on emissions reduction targets.
❓ 본문에 따르면, 정책 입안자들이 기후 티핑 포인트를 이해하는 것이 왜 중요한가?
A. A. 그들은 임계값이 정확히 언제 초과될지 예측할 수 있기 때문이다.
B. B. 예방적 조치가 되돌릴 수 없는 변화를 막기 위해 필요하기 때문이다.
C. C. 기후 변화에 대처하는 데 있어 반응적 조치가 더 효과적이기 때문이다.
D. D. 아마존 열대우림은 삼림 벌채가 중단되면 회복될 것이기 때문이다.
✅ 正确答案
B. Because proactive actions are needed to prevent irreversible changes.
IELTS Reading Tips
Skim the questions first, underline keywords, then locate in the passage
Watch for paraphrasing; correct answers are often reworded
Be wary of absolute statements (all, always, never) — usually wrong
Pay attention to content after transition words (however, but, yet)
Manage time: about 20 minutes per passage; skip difficult questions first