The reason for the high variability of rainfall in the northwestern part of Madhya Pradesh is:

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Correct — A, low rainfall. Rainfall variability is measured as the coefficient of variation, C.V. = (standard deviation ÷ mean rainfall) × 100. The mean sits in the denominator, so the smaller a region's average rainfall, the larger the percentage swing produced by the same absolute departure. The relationship is inverse and it holds across India: areas receiving over 100 cm a year show variability under 25 per cent, areas receiving 50–100 cm show 25–50 per cent, and areas receiving under 50 cm show over 50 per cent. Physically, a dry region lies at the outer margin of monsoon penetration and depends on a handful of depressions reaching it — miss two of them and the season collapses, whereas a wet region has so many rain-days that one weak spell barely dents the total. North-western Madhya Pradesh (the Gwalior–Chambal tract of Bhind, Morena, Sheopur and Datia) is the driest corner of a state whose rainfall falls steadily from the south-east to the north-west, which is precisely why its rainfall is the least dependable.

Why the other options are wrong — (b) The exact inverse of the truth. India's least variable rainfall — under 25 per cent — is found on the west coast, the Western Ghats and in the north-east, i.e. the regions of heaviest rainfall. Abundant rain means many rain-days and a dependable total.  (c) North-western MP is genuinely hot in summer, which makes this tempting, but temperature is a companion of aridity, not the measure behind variability. Coastal and north-eastern India are also hot yet have the country's most dependable rainfall — so high temperature by itself does not produce high variability.  (d) Continuous, steady rain is the signature of low variability, not high. The north-west of the state receives its rain in a few short bursts from passing monsoon depressions rather than continuously, and it is that dependence on a small number of spells which makes the total erratic.

Concept: Rainfall has two separate attributes — how much and how dependable. Dependability is expressed by the coefficient of variation of annual rainfall, C.V. = (standard deviation ÷ mean) × 100, which reports the departure from the long-term average as a percentage. Because the mean is the divisor, variability rises as mean rainfall falls, so India's driest regions are also its most unreliable ones. This is why drought is a recurring feature of low-rainfall belts such as western Rajasthan and the interior Deccan, and why irrigation, not just rainfall totals, decides agriculture there.

State PCS 2026 Q72 — Madhya Pradesh GK PYQ with Answer

State PCS 2026 Q72 — Madhya Pradesh GK PYQ with Answer