El Niño-Southern Oscillation (ENSO) and Indian Climate
Geography
- PYQs8
- Articles1
Background
El Niño is a critical factor in understanding India's climate variability, particularly monsoon performance, drought frequency, and associated impacts on agriculture, water resources, and disaster management. Its predictability is vital for national planning.
The El Niño-Southern Oscillation (ENSO) is a major climate phenomenon characterized by periodic warming (El Niño) and cooling (La Niña) of sea surface temperatures in the central and eastern tropical Pacific Ocean. It significantly influences global weather patterns, including the strength and distribution of the Indian monsoon.
Facts & tables
- Current Status
- El Niño is near-certain through the heart of the upcoming monsoon season.
- Historical Correlation
- Approximately 60% of El Niño years since 1951 have brought deficient or below-normal rains to India.
- Past Droughts
- Severe droughts in India (e.g., 2002, 2009, 2014, 2015) were associated with El Niño events.
- Counteracting Factors
- Indian Ocean Dipole (IOD) can sometimes counteract El Niño's negative impact, but reliance on it is cautioned.
| Type | Reference |
|---|---|
| Conceptual area | Climate Change & Conventions |
| Conceptual area | Biogeography & Ecosystems |
Prelims angle
Prelims angle: Multi-statement analysis
Prelims angle: Conceptual understanding
- El Niño: warming of eastern tropical Pacific.
- Strongly linked to deficient Indian monsoons (60% correlation).
- Associated with major droughts in India.
- Indian Ocean Dipole (IOD) can sometimes moderate its effects.
- Crucial for understanding India's climate variability and disaster preparedness.
Treaty = agreement between states; body = institution.
| Year | Framing tags |
|---|---|
| 2025 | Multi-statement analysis, Factual recall |
| 2025 | Statement-based questions, Conceptual understanding |
| 2024 | Multi-statement analysis, Factual recall |
| 2024 | Conceptual understanding, Multi-statement analysis |
| 2023 | Statement-based questions, Conceptual understanding |
| 2021 | Statement-based questions, Conceptual understanding |
| 2020 | Statement-based questions, Conceptual understanding |
| 2017 | Multi-statement analysis, Conceptual understanding |
Timeline
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Climate Change & Conventions
Conceptual area
-
Biogeography & Ecosystems
Conceptual area
-
Prelims 2017
Multi-statement analysis, Conceptual understanding
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Prelims 2020
Statement-based questions, Conceptual understanding
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Prelims 2021
Statement-based questions, Conceptual understanding
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Prelims 2023
Statement-based questions, Conceptual understanding
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Prelims 2024
Multi-statement analysis, Factual recall
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Prelims 2024
Conceptual understanding, Multi-statement analysis
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Prelims 2025
Multi-statement analysis, Factual recall
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Prelims 2025
Statement-based questions, Conceptual understanding
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Missed call: On India and the southwest monsoon
El Niño, a warming of the Pacific, is strongly correlated with deficient Indian monsoons, posing a significant threat to agriculture and water security, necessitating proactive government measures despite potential mitigating factors like the Indian Ocean Dipole.
See also
Past papers
2017–2025 · 7 questions
In the news
Missed call: On India and the southwest monsoon
El Niño, a warming of the Pacific, is strongly correlated with deficient Indian monsoons, posing a significant threat to agriculture and water security, necessitating proactive government measures despite potential mitigating factors like the Indian Ocean Dipole.
Try these PYQs
With reference to ‘Indian Ocean Dipole (IOD)’ sometimes mentioned in the news while forecasting Indian monsoon, which of the following statements is/are correct?
1. IOD phenomenon is characterized by a difference in sea surface temperature between tropical Western Indian Ocean and tropical Eastern Pacific Ocean.
2. An IOD phenomenon can influence El Nino’s impact on the monsoon.
Select the correct answer using the code given below:
Statement 1 is Incorrect: The IOD phenomenon is characterised by a difference in sea surface temperature between the tropical Western Indian Ocean and the tropical Eastern Indian Ocean, not the Eastern Pacific Ocean. During a positive IOD, the western Indian Ocean is warmer than the eastern Indian Ocean, and vice versa for a negative IOD. Statement 2 is Correct: The IOD phenomenon can indeed influence El Nio's impact on the Indian monsoon. El Nio itself is a climate pattern in the Pacific Ocean, but it can interact with the IOD. Depending on the phases of both phenomena (positive/negative IOD and El Nino/La Nina), the overall impact on the Indian monsoon rainfall can be amplified or weakened. Hence, option B is the correct answer.
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 meters 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.
Select the correct answer using the code given below:
Statement 1 is incorrect. OMT is measured up to the depth of the 26°C isotherm, but the 129-meter depth mentioned in the southwestern Indian Ocean during January-March is incorrect. The depth of the 26°C isotherm can vary depending on the region and season. Statement 2 is correct. OMT collected during January-March helps in predicting the amount of rainfall during the monsoon. It is used to assess whether rainfall will be more or less than the long-term average, as variations in OMT influence monsoon behaviour. Hence, option B is the correct answer.
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 :
Understanding Isotherms and Their Behavior * Isotherms are lines on a map connecting points with the same temperature. * January is a winter month in the Northern Hemisphere. * Land and Water Heating Differences: Land heats up and cools down faster than water. This leads to significant temperature differences between continents and oceans in winter. Statement 1: Correct * In January, continents are colder than oceans in the Northern Hemisphere. * Isotherms bend northward over oceans, indicating warmer temperatures. * Isotherms bend southward over continents, indicating colder temperatures. Statement 2: Incorrect * The Gulf Stream and North Atlantic Drift are warm ocean currents, not cold. * These currents bring warm water from the tropics towards Europe, making the North Atlantic relatively warmer in winter. * Isotherms bend northward over the North Atlantic due to these warm currents. Conclusion: Only statement 1 is a correct inference from isothermal maps in January.
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?
Statement 1 is correct. The trade winds in the tropical zone blow from east to west, causing the western sections of the oceans to be warmer than the eastern sections. This is because these winds push the warm surface waters towards the west. Statement 2 is correct. On the other hand, in the temperate zone, the westerlies blow from west to east. These winds push the warm waters towards the eastern sections of the oceans, making them warmer than the western sections. Therefore, both statements are correct.
Consider the following statements:
Statement I:
In the context of effect of water on rocks, chalk is known as a very permeable rock whereas clay is known as quite an impermeable or least permeable rock.
Statement II:
Chalk is porous and hence can absorb water.
Statement III:
Clay is not at all porous.
Which one of the following is correct in respect of the above statements?
✅ Statement I: Correct
Chalk is permeable (water passes easily); clay is impermeable (water passes poorly). ✅ Statement II: Correct
Chalk is porous, with many small holes that hold water, making it permeable. ❌ Statement III: Incorrect
Clay is porous but with very tiny pores that restrict water flow; it is impermeable but not non-porous. Correct Answer: Only Statements I and II are correct; Statement II explains Statement I.
Show 3 more PYQs
Consider the following pairs:
Country – Resource-rich in
I. Botswana : Diamond
II. Chile : Lithium
III. Indonesia : Nickel
In how many of the above rows is the given information correctly matched?
This question checks knowledge of countries known for major natural resources that play key roles in global markets. ✅ I. Botswana : Diamond – Correct
* Botswana is a top global producer of diamonds, vital to its economy. ✅ II. Chile : Lithium – Correct
* Chile has vast lithium reserves in the Atacama Desert and is a leading global supplier. ✅ III. Indonesia : Nickel – Correct
* Indonesia is the world’s largest producer of nickel, crucial for batteries and steel.
Consider the following statements :
Statement-I: The temperature contrast between continents and oceans is greater during summer than in winter.
Statement-II: The specific heat of water is more than that of land surface.
Which one of the following is correct in respect of the above statements?
Statement-I is incorrect: The temperature contrast between land and ocean is actually greater in winter, not in summer. In winter, land loses heat quickly and becomes much colder, while the ocean retains heat and stays relatively warm → large contrast.
In summer, both land and ocean warm up, but the difference is less pronounced compared to winter → smaller contrast. Statement-II is correct: Water has a higher specific heat capacity than land. It heats up and cools down more slowly, which explains why oceans have a moderating influence on temperature.
Consider the following statements:
Statement-I : Sumed pipeline is a strategic route for Persian Gulf oil and natural gas shipments to Europe.
Statement-II : Sumed pipeline connects the Red Sea with the Mediterranean Sea.
Which one of the following is correct in respect of the above statements?
Statement I is correct. The Sumed Pipeline is indeed a significant route for transporting oil and natural gas from the Persian Gulf to Europe. It bypasses the Suez Canal, offering an alternative path for these resources. Statement II is also correct. The Sumed Pipeline physically connects the Red Sea (where oil and gas are loaded onto ships from the Persian Gulf) with the Mediterranean Sea, providing a direct route for them to reach European ports. The connection between the Red Sea and the Mediterranean Sea established by the Sumed Pipeline directly explains its strategic importance for transporting oil and gas to Europe. Statement II provides the geographical context for how Statement I functions.