"Record Sea Surface Temperatures Signal Urgent Need for Climate Adaptation"
Sea Surface Temperature (SST)
temperature of the ocean's uppermost layer, a key climate and weather indicator.
El Niño
periodic warming of central-eastern Pacific surface waters, weakening trade winds and raising global SSTs.
Oceans cover about 71% of the Earth's surface and play a central role in regulating the planet's climate. They absorb solar radiation, redistribute heat through currents, and exchange gases with the atmosphere. According to the IPCC and NASA, oceans have absorbed more than 90% of the excess heat generated by global warming since the industrial era. This buffering role has slowed the pace of atmospheric warming. However, it has come at a growing cost to marine systems and, increasingly, to the stability of weather patterns on land.
Sea surface temperature (SST) is one of the most closely monitored climate indicators. It influences tropical cyclone formation, monsoon behaviour, marine biodiversity, and sea-level rise. The El Niño-Southern Oscillation (ENSO) is a key driver of interannual SST variability. During an El Niño event, warm water from the central Pacific drifts eastward, suppressing the normal upwelling of cold water and raising global average SSTs. When El Niño combines with the long-term warming trend from greenhouse gas emissions, SST anomalies can reach unprecedented levels. The Sendai Framework for Disaster Risk Reduction 2015–2030 and successive UNFCCC agreements recognise ocean warming as a cross-cutting risk requiring both mitigation and adaptation responses.
India's vulnerability to ocean warming is structural. With a coastline exceeding 10,000 km, India's coastal population, fisheries, agriculture, and urban infrastructure are directly exposed to rising seas, intensifying cyclones, and erratic monsoons, all of which are linked to SST changes.
Sea surface temperature is measured as the temperature of the top layer of the ocean, typically the uppermost metre. Normally, global SSTs peak in March and April. The previous all-time record was 21.09°C, set in March 2024. This record was surpassed when SSTs reached 21.1°C, driven by the combined effect of a rapidly intensifying El Niño and the underlying trend of anthropogenic global warming. Crucially, this new peak occurred in August, outside the normal seasonal maximum, signalling a disruption of the ocean's thermal calendar itself.
Ocean warming operates through several interconnected mechanisms. First, warmer surface waters increase evaporation, loading the atmosphere with moisture and intensifying precipitation events and cyclones. Second, thermal expansion of seawater contributes directly to sea-level rise. Global average sea level was approximately 11 centimetres higher by end-2025 than in January 1993. …
Which of the following is/are correct inference/inferences from isothermal maps in the month of January?
1.The isotherms deviate to the north over the ocean and to the south over the continent.
2.The presence of cold ocean currents, Gulf Stream and North Atlantic Drift make the North Atlantic Ocean colder and the isotherms bend towards the north.
Select the answer using the code given below:
Consider the following statements:
1.In the tropical zone, the western sections of the oceans are warmer than the eastern sections owing to the influence of trade winds.
2.In the temperate zone, westerlies make the eastern sections of oceans warmer than the western sections.
Which of the statements given above is/are correct?
With reference to Ocean Mean Temperature (OMT), which of the following statements is/are correct?
1.OMT is measured up to a depth of 26°C isotherm which is 129 metres in the south-western Indian Ocean during January-March.
2.OMT collected during January-March can be used in assessing whether the amount of rainfall in monsoon will be less or more than a certain long-term mean.
Which of the statements given above is/are correct?
Assess the impact of global warming on the coral life system with examples.
What are the consequences of spreading of 'Dead Zones' on marine ecosystem?
Consider the following statements regarding ocean temperature and global climate:
1.Oceans have absorbed more than 90 per cent of the excess heat generated by global warming.
2.In the tropical zone, trade winds make the eastern sections of oceans warmer than the western sections.
3.Ocean Mean Temperature (OMT) data collected during January–March can help predict Indian monsoon rainfall relative to the long-term mean.
Which of the statements given above is/are correct?
Consider the following statements about sea-level rise:
1.Thermal expansion of ocean water is one of the contributors to sea-level rise.
2.Global average sea level was approximately 11 centimetres higher by end-2025 than in January 1993.
3.Sea-level rise has no effect on coral reef ecosystems.
Which of the statements given above is/are correct?
Match the following ocean-climate phenomena with their correct descriptions:
List I (Phenomenon) — List II (Description)
A.El Niño — 1. Warm Pacific water drifts eastward, weakening trade winds
B.Ocean Mean Temperature — 2. Measured to the depth of the 26°C isotherm; used in monsoon prediction
C.Coral Bleaching — 3. Expulsion of zooxanthellae by corals under thermal stress
D.Dead Zone — 4. Hypoxic ocean area where dissolved oxygen falls below 2 mg/litre
Select the correct answer using the code given below:
With reference to the role of oceans in the global climate system, consider the following statements:
1.The oceans are normally at their warmest in March and April.
2.Warming of ocean surfaces reduces the oceans' capacity to regulate weather patterns on land.
3.Ocean warming contributes to sea-level rise only through melting of polar ice caps, not through any other mechanism.
How many of the above statements are correct?
Assertion (A): Even if global greenhouse gas emissions were sharply reduced today, the consequences of past ocean warming would persist for years.
Reason (R): Oceans have a high heat capacity and release stored heat slowly, making the warming trend difficult to reverse on short timescales.
Select the correct answer using the code given below:
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