Topic: changes in critical geographical features (including water-bodies and ice-caps) and in flora and fauna and the effects of such changes
Q1. “Record sea-surface temperatures cannot be explained by greenhouse warming alone.” Explain the role of ocean–atmosphere interactions in producing large-scale SST anomalies. Examine how El Niño can amplify such anomalies. (10 M)
Difficulty Level: Medium
Reference: DTE
Why the question
Record sea-surface temperatures (SSTs) with ocean–atmosphere interactions and the intensification of El Niño, testing conceptual understanding of contemporary climatological processes.
Key Demand of the question
Establish why greenhouse warming alone cannot explain record SST anomalies and explain the role of ocean–atmosphere interactions in generating them. Further, examine the mechanisms through which El Niño can amplify SST anomalies.
Structure of the Answer:
Introduction
Introduce oceans as major heat reservoirs and distinguish long-term anthropogenic warming from shorter-term ocean–atmosphere variability.Body
- Justification of the statement: Briefly establish how anthropogenic warming provides the baseline while natural climate variability determines the magnitude, timing and spatial distribution of SST anomalies.
- Role of ocean–atmosphere interactions: Explain how winds, currents, upwelling, thermocline variations and air–sea heat exchanges generate and sustain large-scale SST anomalies.
- Amplification by El Niño: Examine how weakening trade winds, reduced upwelling, thermocline changes and coupled positive feedbacks can reinforce Pacific warming and wider SST anomalies.
Conclusion
Conclude by emphasizing the interaction between long-term anthropogenic warming and natural climate variability in shaping record ocean temperatures and associated climate extremes.
