Previous Year Question
If there were no Himalayan ranges, what would have been the most likely geographical impact on India?
Much of the country would experience the cold waves from Siberia.
Indo-gangetic plain would be devoid of such extensive alluvial soils.
The pattern of monsoon would be different from what it is at present.
Which of the statement(s) given above is/are correct?
Only 1
1 and 3
2 and 3
1, 2 and 3
Correct Answer: D
Detailed Solution
All three statements are correct.
Statement 1—Correct
The Himalayas act as an enormous climatic barrier between the Indian subcontinent and Central Asia.
During winter, extremely cold and dry continental air masses develop over Siberia and Central Asia.
The Himalayas prevent these cold winds from directly entering the Indian subcontinent.
In the absence of the Himalayas, there would be no massive physical barrier to these air masses, and large parts of northern and interior India would experience more intense cold waves.
The winter climate of northern India would consequently be colder and more continental than it is at present.
Statement 2—Correct
The Indus-Ganga-Brahmaputra Plain was formed from enormous quantities of alluvium brought by rivers originating in the Himalayas.
Himalayan rivers erode the mountainous region and transport sand, silt, clay and other sediments to the plains.
Long-term deposition of these sediments created the extensive, level and fertile Northern Plains.
Without the Himalayas, the Himalayan river system and the supply of such enormous quantities of sediments would not exist.
Consequently, the Indo-Gangetic Plain would not possess its present extensive cover of alluvial soil.
Statement 3—Correct
The Himalayas influence the Indian monsoon in several ways:
They prevent the southwest monsoon winds from escaping towards the north.
Moist winds are forced to rise against the mountains, cool and produce rainfall.
The Himalayas help redirect monsoon winds eastward and westward within the Indian subcontinent.
The thermal influence of the Himalayas and the Tibetan Plateau affects summer pressure conditions and atmospheric circulation.
Without the Himalayas, the route of monsoon winds, spatial distribution of rainfall, strength of the monsoon and duration of rainfall would differ from the present pattern.