UPSC Prelims Practice Questions — Models struggled to predict the 2026 monsoon’s rapid changes

Q1. Sea-surface temperature anomalies over which one of the following areas are most commonly used as the principal index for monitoring the status of the El Niño Southern Oscillation?

  • A. The Niño 1+2 area off the coasts of Peru and Ecuador, where cold coastal upwelling is suppressed
  • B. The western equatorial Indian Ocean, where anomalous warming marks a positive dipole event
  • C. The Niño 3.4 area of the central and east-central equatorial Pacific Ocean
  • D. The southern Indian Ocean near 25°S–35°S, where a semi-permanent high-pressure belt builds up

Q2. Consider the following descriptions of components and phases of the El Niño Southern Oscillation: 1. La Niña — colder-than-average sea surface temperatures in the central and eastern Pacific accompanied by an intensification of the prevailing east-to-west surface winds. 2. Southern Oscillation — the oceanic component of the phenomenon, tracked through sea-surface temperature anomalies of the tropical Pacific. 3. El Niño — a period of sea-surface warming that suppresses the nutrient-rich cold upwelling off Peru and Ecuador and typically lasts between 12 and 18 months. 4. El Niño Southern Oscillation — a phenomenon that recurs in irregular cycles of two to seven years and presents three phases. Which of the above is/are correctly identified?

  1. La Niña — colder-than-average sea surface temperatures in the central and eastern Pacific accompanied by an intensification of the prevailing east-to-west surface winds.
  2. Southern Oscillation — the oceanic component of the phenomenon, tracked through sea-surface temperature anomalies of the tropical Pacific.
  3. El Niño — a period of sea-surface warming that suppresses the nutrient-rich cold upwelling off Peru and Ecuador and typically lasts between 12 and 18 months.
  4. El Niño Southern Oscillation — a phenomenon that recurs in irregular cycles of two to seven years and presents three phases.
  • A. 1 and 3 only
  • B. 2 and 4 only
  • C. 1, 3 and 4 only
  • D. 1, 2 and 4 only

Q3. Consider the following as characteristics of a positive phase of the Indian Ocean Dipole: 1. Anomalously warm sea surface temperatures in the western equatorial Indian Ocean together with anomalously cool ones in the eastern part of the basin. 2. Enhancement of atmospheric convection over the eastern Indian Ocean and its suppression over the western Indian Ocean. 3. A weakening or reversal of the climatological zonal sea-surface temperature gradient, with anomalous winds blowing from east to west along the equator. 4. A suppression of southwest monsoon rainfall over the Indian subcontinent, broadly similar in direction to the effect of El Niño. Which of the above is/are correctly identified?

  1. Anomalously warm sea surface temperatures in the western equatorial Indian Ocean together with anomalously cool ones in the eastern part of the basin.
  2. Enhancement of atmospheric convection over the eastern Indian Ocean and its suppression over the western Indian Ocean.
  3. A weakening or reversal of the climatological zonal sea-surface temperature gradient, with anomalous winds blowing from east to west along the equator.
  4. A suppression of southwest monsoon rainfall over the Indian subcontinent, broadly similar in direction to the effect of El Niño.
  • A. 1 and 2
  • B. 1 and 3
  • C. 2 and 4
  • D. 1, 3 and 4

Q4. As assessed in the India Meteorological Department's first Long Range Forecast for the 2026 southwest monsoon season, issued in April 2026, the state of the Indian Ocean Dipole prevailing at the time of issue and the state expected towards the end of the season were, respectively:

  • A. Neutral conditions at the time of issue, with positive IOD conditions likely to develop towards the end of the season
  • B. Negative IOD conditions at the time of issue, with neutral conditions likely to be reached towards the end of the season
  • C. Positive IOD conditions at the time of issue, with negative IOD conditions likely to develop towards the end of the season
  • D. Neutral conditions at the time of issue, with negative IOD conditions likely to develop towards the end of the season

Q5. Consider the following statements comparing the successive Long Range Forecasts issued by the India Meteorological Department for the 2026 southwest monsoon season: 1. The first Long Range Forecast placed seasonal rainfall at 92 per cent of the Long Period Average, while the updated forecast issued at the end of May lowered this to 90 per cent. 2. The probability assigned to deficient seasonal rainfall rose from 35 per cent in the first forecast to 60 per cent in the updated forecast. 3. The Long Range Forecast Outlook for the second half of the season placed August–September rainfall in the above-normal category at 105 per cent of the Long Period Average. Which of the statements given above is/are correct?

  1. The first Long Range Forecast placed seasonal rainfall at 92 per cent of the Long Period Average, while the updated forecast issued at the end of May lowered this to 90 per cent.
  2. The probability assigned to deficient seasonal rainfall rose from 35 per cent in the first forecast to 60 per cent in the updated forecast.
  3. The Long Range Forecast Outlook for the second half of the season placed August–September rainfall in the above-normal category at 105 per cent of the Long Period Average.
  • A. 1 only
  • B. 2 and 3 only
  • C. 1 and 2 only
  • D. 1, 2 and 3

Q6. With reference to the Long Period Average against which the India Meteorological Department expresses its seasonal rainfall forecasts, which one of the following statements is correct?

  • A. It is recomputed every year so that the seasonal forecast is always expressed against the immediately preceding decade of rainfall
  • B. It is the country-wide average southwest monsoon rainfall for the period 1971–2020, currently taken as 868.6 mm
  • C. It is a fixed constant that has never been revised since the department began issuing seasonal monsoon forecasts
  • D. It is the average rainfall of the monsoon core zone alone, and applies exclusively to the four broad homogeneous regions

Q7. During the 2026 southwest monsoon season, which one of the following States recorded the largest share of its area under drought conditions?

  • A. Manipur
  • B. Jharkhand
  • C. Meghalaya
  • D. Chhattisgarh

Q8. Consider the following statements about the 2026 southwest monsoon season in India as compared with the preceding year: 1. Kharif sowing as on 10 July 2026, at about 53 million hectares, was around 16 per cent lower than the area covered on the corresponding date a year earlier. 2. Rainfall in June 2026 was about 40 per cent below normal, making it the fifth-driest June for the country in a century. 3. Every one of the 111 high-priority districts flagged by the Government as vulnerable to El Niño was already rainfall-deficient by the middle of July 2026. Which of the statements given above is/are correct?

  1. Kharif sowing as on 10 July 2026, at about 53 million hectares, was around 16 per cent lower than the area covered on the corresponding date a year earlier.
  2. Rainfall in June 2026 was about 40 per cent below normal, making it the fifth-driest June for the country in a century.
  3. Every one of the 111 high-priority districts flagged by the Government as vulnerable to El Niño was already rainfall-deficient by the middle of July 2026.
  • A. 1 and 2 only
  • B. 2 and 3 only
  • C. 1 and 3 only
  • D. 1, 2 and 3

Q9. Under India's National Monsoon Mission launched in 2012, the sub-mission dealing with prediction on the extended range to seasonal time scale is coordinated by which one of the following institutions?

  • A. National Centre for Medium Range Weather Forecasting, Noida
  • B. Indian National Centre for Ocean Information Services, Hyderabad
  • C. National Centre for Earth Science Studies, Thiruvananthapuram
  • D. Indian Institute of Tropical Meteorology, Pune

Q10. According to the India Meteorological Department, how much rainfall, and over what extent of area, must be recorded for an event to be classified as a cloudburst?

  • A. 50 mm of rainfall in one hour, irrespective of the area over which it falls
  • B. 100 mm of rainfall in twenty-four hours over an area of about 20–30 sq km
  • C. 100 mm of rainfall in one hour over an area of about 20–30 sq km
  • D. Any rainfall exceeding 200 mm in a day, wherever in the country it occurs

Q11. The build-up of which one of the following semi-permanent pressure systems is the principal source of the cross-equatorial low-level flow known as the Somali Jet, whose establishment precedes the onset of the southwest monsoon?

  • A. The Azores High, a semi-permanent anticyclone over the eastern North Atlantic near 30°N
  • B. The Mascarene High, a high-pressure belt between about 25°S and 35°S in the southern Indian Ocean
  • C. The Siberian High, a cold-season anticyclone centred over the interior of central Asia
  • D. The Tibetan anticyclone, an upper-tropospheric system over the Tibetan Plateau in summer

Q12. Consider the following statements regarding the Sixth Assessment Report of the Intergovernmental Panel on Climate Change and its assessment of the Asian monsoon: 1. Monsoon land precipitation is likely to increase over East, Southeast and South Asia, mainly on account of increasing moisture convergence under elevated temperature. 2. In the near term, South Asian and Southeast Asian monsoon precipitation change will be dominated by the effects of internal variability. 3. Anthropogenic aerosols have a negligible influence on sub-regional monsoon precipitation change, which is driven entirely by greenhouse gas forcing. 4. Increasing land–sea thermal contrast, together with rising atmospheric moisture, is projected to intensify South Asian summer monsoon precipitation. Which of the above is/are NOT correct?

  1. Monsoon land precipitation is likely to increase over East, Southeast and South Asia, mainly on account of increasing moisture convergence under elevated temperature.
  2. In the near term, South Asian and Southeast Asian monsoon precipitation change will be dominated by the effects of internal variability.
  3. Anthropogenic aerosols have a negligible influence on sub-regional monsoon precipitation change, which is driven entirely by greenhouse gas forcing.
  4. Increasing land–sea thermal contrast, together with rising atmospheric moisture, is projected to intensify South Asian summer monsoon precipitation.
  • A. 1 and 3
  • B. 3 only
  • C. 2 and 4
  • D. 1, 2 and 4