Question

Why parts of Rajasthan, Gujarat and the leeward side of the Western Ghats drought-prone?

Answer 1

Hint:
Almost one-sixth of India's overall geographical area, with 12% of the population, is vulnerable to drought;
The areas with an annual rainfall of up to 60 cm are the most prone.
A drought-prone region is characterised as one in which the risk of a drought year is greater than 20%.
A persistent drought-prone environment is one in which the risk of a drought year is greater than 40%.

Complete solution:
Reason for these areas to be drought-prone-
- The areas of Rajasthan, Gujarat and the leeward side of the Western Ghats are vulnerable to drought, as the parts of Rajasthan, which fall under the rain shadows of Aravalli and Aravalli, lie parallel.
- South-westerly winds, low mountains, and Gujarat can't deter rainy clouds, and the leeward side of the Western Ghats is vulnerable to drought, as the Western Ghats Mountains is very high and the highest rainfall is on the leeward side of the coast.

Geology of Western Ghats:
- The Western Ghats are the deficient and degraded edge of the Deccan Plateau.
- Geological data suggests that some 150 million years ago they were formed after the break-up of the Gondwana supercontinent.
- Geophysical data suggests that the western coast of India came into being some 100 to 80 mi after it split away from Madagascar.
- After the break-up, the western coast of India may have emerged as an abrupt cliff at an altitude of some 1,000 m (3300 ft).
- Basalt is the primary rock located in the hills with a thickness of 3 km (2 mi).
- Residual laterites and bauxite ores are also present in the southern hills.

Note:
Leeward Side:
- The leeward side is behind the mountains, not facing the seas. That's the dry, arid part of it.
- Now, why are each side the way it is? Cool, hot air is forced to climb up because of the mountains, getting cooler with rising altitudes.