Indian Monsoon

During monsoon there can be gaps in rainfall. This can affect agriculture and water availability.

Delay or deficiency of monsoon can affect sowing and growth of crops. Therefore rainfall timing is important.

The Thar has low moisture and greater dryness. Therefore monsoon rainfall is relatively low there.

The retreating monsoon begins withdrawing from northern India after the rainy season. This is called monsoon withdrawal.

Retreating winds can bring moisture from the Bay of Bengal and give rainfall to the Tamil Nadu coast. It is important for the south-eastern coast.

The north-east monsoon gives rainfall to the south-eastern coast including Tamil Nadu. Remember it with winter rainfall.

A large population and agriculture in India are affected by monsoon rainfall. Therefore the monsoon has great economic importance.

The governing concept is the dependence of seasonal water supply on monsoon rainfall. A weak monsoon generally brings less or poorly distributed rain than expected. If the deficiency is significant, reservoirs, rivers, groundwater recharge and soil moisture may not receive enough water. This can create water scarcity, reduce crop yields and increase the possibility of drought, especially in rain-fed agricultural areas. Therefore option A is the most likely effect. A weak monsoon cannot freeze the sea in the usual climatic conditions of India; it cannot change latitude, which is a geographic coordinate, and it cannot make mountains grow, since mountain building is a long-term geological process. The exact severity depends on duration, location and water storage, but drought and shortage are the relevant likely outcomes.

Very heavy rainfall can fill rivers and low-lying areas with water. This creates flood conditions.

In summer the land area of North India heats up and forms low pressure. This helps attract the monsoon.

The Himalaya blocks monsoon winds from moving further north and helps rainfall. It is a major control of Indian climate.

Monsoon winds act differently according to mountains, distance and direction. Therefore rainfall distribution is unequal.

The south-west monsoon brings rainfall to different regions through two branches. Remember the routes of the branches.

The Bay of Bengal branch gives rainfall as it moves ahead and loses moisture. Therefore rainfall may decrease westward.

Monsoon rainfall is called seasonal because it is concentrated in a particular part of the year rather than being evenly distributed through all months. In India, the main southwest monsoon rainfall generally occurs from June to September. The winds change direction seasonally, bring moisture from the surrounding seas and produce most of the annual rainfall during this period. Therefore option A correctly explains the term seasonal rainfall. Equal rainfall every day is not a feature of the monsoon, and monsoon rain is not snowfall.

Seasonal does not mean that rain falls continuously or with the same intensity every day from June to September. There may be wet spells, breaks and regional differences. It means that the major rainy season is linked to a recurring period of the annual wind cycle. The relation with winds is essential, because seasonal heating and pressure changes help draw moisture-bearing winds toward the land. Thus the timing of rainfall, not daily equality, is the reason option A is correct.

Monsoon does not arrive at the same time and in the same amount every year. This uncertainty becomes a challenge for agriculture.

Kharif crops are sown with the arrival of monsoon. Therefore timely monsoon rainfall is very important.

Monsoon rainfall fills reservoirs and some water seeps into the ground. This can improve water resources.

During retreating monsoon temperature slowly falls and moisture can cause rain on the south-eastern coast. Treat it as a transition period.

In winter north-east winds blow from land and generally have low moisture. But they can pick moisture from the Bay of Bengal and give rain in Tamil Nadu.