Give reasons to explain each of the following:
a. Northern Plains would have been much drier if the Himalayas were not in their present
position.
Answers
Answer:
Without the Himalayas being there, which acts as a wall - a natural barrier to the winds - the plains would have to face the harsh Siberian winds blowing southwards making the whole North Indian region much colder. Also this wall prevents the monsoon winds coming all the way from bay of Bengal, going further north. Without the wall, we'd receive much lesser rains in the region.
In the absence of Himalayan glaciers, the three major river systems (Ganges, Indus, Brahmputra) would either not be there, or they wouldn't be as huge as they're. If these rivers would somehow get formed by the water draining in the monsoon (whatever is left of the monsoon without Himalayas being there), they won't be perennial anymore as melting snow round the year is the main source of water for these rivers and their tributaries.
These plains we're talking about are floodplains of the Indus-Ganga-Brahmputra river systems, and without the rich fertile soil deposited in the river basins, the current North Indian plains as we know it, wouldn't exist. Instead of the plains with extremely high fertile soil, the land would be more like Tibetan or Deccan plateau. In the absence of fertile lands, the thick forests wouldn't be there which would severely alter the climate. One of the major impacts would be lesser rainfall as a result of lesser evaporation which would further disturb the natural water cycle.
The cumulative effect of all this would be a much drier and much colder North India with less greenery, and less geographical diversity.
Explanation:
Without the Himalayas being there, which acts as a wall - a natural barrier to the winds - the plains would have to face the harsh Siberian winds blowing southwards making the whole North Indian region much colder. Also this wall prevents the monsoon winds coming all the way from bay of Bengal, going further north. Without the wall, we'd receive much lesser rains in the region.
In the absence of Himalayan glaciers, the three major river systems (Ganges, Indus, Brahmputra) would either not be there, or they wouldn't be as huge as they're. If these rivers would somehow get formed by the water draining in the monsoon (whatever is left of the monsoon without Himalayas being there), they won't be perennial anymore as melting snow round the year is the main source of water for these rivers and their tributaries.
These plains we're talking about are floodplains of the Indus-Ganga-Brahmputra river systems, and without the rich fertile soil deposited in the river basins, the current North Indian plains as we know it, wouldn't exist. Instead of the plains with extremely high fertile soil, the land would be more like Tibetan or Deccan plateau. In the absence of fertile lands, the thick forests wouldn't be there which would severely alter the climate. One of the major impacts would be lesser rainfall as a result of lesser evaporation which would further disturb the natural water cycle.
The cumulative effect of all this would be a much drier and much colder North India with less greenery, and less geographical diversity.