Previous Year Question
The winter rains caused by Western disturbance in North Western Plain of India gradually decreases from
East to West
West to East
North to South
South to North
Correct Answer: B
Detailed Solution
The major cause of winter rainfall over north-western India is the Western Disturbances. These are mainly extra-tropical weather systems originating around the Mediterranean region and moving towards India through Iran, Afghanistan and Pakistan with the westerly circulation.
During winter, they cause rainfall particularly over Punjab, Haryana, Delhi and western Uttar Pradesh, and rainfall and snowfall over the western Himalayan region.
In the northern plains, rainfall associated with Western Disturbances decreases from west to east. According to NCERT, winter precipitation decreases west to east in the plains and north to south in the mountains.
This happens because Western Disturbances enter India from the north-west and move eastward. As they proceed eastward, their moisture and influence gradually weaken, resulting in lower winter rainfall towards the eastern parts compared with Punjab and Haryana.
Although the amount of rainfall is small, it is agriculturally very useful. Winter rainfall is particularly important for Rabi crops such as wheat, gram and mustard.