"El Niño threat persists for rabi crops despite July monsoon revival"
Low-Pressure System (LPS)
synoptic-scale weather system over Bay of Bengal that delivers concentrated monsoon rainfall inland
Long Period Average (LPA)
baseline average rainfall (~887 mm) against which seasonal monsoon performance is measured
India's Southwest Monsoon (June–September) is the agricultural lifeline of the country, delivering approximately 75% of annual rainfall against a Long Period Average (LPA) of ~887 mm. The monsoon's behaviour is critically shaped by the El Niño–Southern Oscillation (ENSO) — a naturally recurring ocean-atmosphere coupled phenomenon in the tropical Pacific. El Niño, the warm phase of ENSO, is defined when sea surface temperatures (SSTs) in the Niño 3.4 region of the central-eastern equatorial Pacific exceed the climatological mean by +0.5°C for five consecutive overlapping three-month periods. Historically, roughly 60% of strong El Niño years have coincided with below-normal monsoon rainfall in India, though modulating factors such as the Indian Ocean Dipole (IOD) and the Madden-Julian Oscillation (MJO) can offset or amplify this suppressive effect.
Kharif crops — sown with the onset of the monsoon and harvested in autumn — include rice, pulses, oilseeds, cotton, and soyabean, and are directly dependent on the June–September rainfall window. Rabi crops (wheat, mustard, potato), sown in October–November and harvested in spring, depend less on monsoon rain but are sensitive to winter temperatures, which El Niño is known to elevate. India's import dependence on oilseeds, pulses, and cotton means that domestic production shortfalls from weather shocks translate rapidly into import bills and global price exposure.
The mechanism by which El Niño suppresses Indian monsoon rainfall operates through the Walker Circulation — the zonal atmospheric loop in the tropical Pacific. Under normal conditions, strong easterly trade winds push warm surface water westward, sustaining rising moist air over the Indo-Pacific Warm Pool and driving monsoon convection over India. During El Niño, trade winds weaken or reverse, warm water shifts eastward toward the central-eastern Pacific, and the Walker Circulation weakens. This induces subsidence (sinking air) over the Indian Ocean, suppressing convective activity and reducing the moisture-laden winds that fuel the Southwest Monsoon.
A critical mechanism for monsoon variability within the season is the formation of Low-Pressure Systems (LPS) — synoptic-scale weather systems that develop over the Bay of Bengal and move inland, delivering concentrated rainfall across central and peninsular India. …
The seasonal reversal of winds is the typical characteristic of
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?
With reference to Low-Pressure Systems (LPS) and the Indian Southwest Monsoon, consider the following statements:
1.A normal June monsoon season witnesses approximately three LPS active over about 11 days.
2.LPS formation over the Bay of Bengal is the primary mechanism delivering rainfall to peninsular and central India during the monsoon season.
3.El Niño conditions directly suppress LPS formation by strengthening easterly trade winds over the Bay of Bengal.
Which of the statements given above is/are correct?
The FAO Food Price Index is best described as:
Consider the following statements about El Niño's impact on Indian agriculture:
1.El Niño's suppressive effect on Indian monsoon rainfall typically manifests with a lag of 1–2 months after the phenomenon intensifies.
2.El Niño raises global temperatures, which can shorten and warm Indian winters, adversely affecting wheat and mustard yields.
3.Historically, all strong El Niño years have resulted in below-normal monsoon rainfall in India.
Which of the statements given above is/are correct?
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