Monsoon in India

Monsoon is an important part of the climate section and is important as the Indian climate is dominated by monsoon and is very significant for the country’s economy and plays an important part in agriculture in India.

Monsoons

The word Monsoon originated from the Arabic word “mawsim”, which means season. Monsoons refer to seasonal winds which are reversed from their directions according to the changing seasons and are hence known to be periodic winds. The monsoons tend to travel from sea to land in summers and from land to sea during winters, which gives rise to the concept of a double system of seasonal winds.

India receives Southwest monsoon winds during the summers and northeast monsoons are received during the winters. The former arises because of the formation of the intense low-pressure system over the Tibetan plateau and the latter does arise because of high-pressure cells which are formed over the Siberian and Tibetan plateaus.

Read More:

1. Mechanism of Monsoons,
2. Burst of Monsoon and Break of Monsoon

Monsoons in India Map

Monsoons in India Map

Southwest Monsoon

The southwest monsoon is caused because of intense low-pressure formation over Tibetan Plateau for intense heating during the summer season; there is a permanent form of high-pressure cell located in the South of the Indian Ocean. The winds of the Southwest monsoon bring heavy rainfall in most parts of the country.

Factors Influencing Onset of Southwest Monsoons

The factors which influence the onset of Southwest Monsoons include:

1. Intense low pressure is formed over the Tibetan plateau.
2. Permanent high-pressure cell in the south of the Indian Ocean.
3. Subtropical jet stream
4. African Easterly stream
5. Inter-Tropical Convergence Zone (ITCZ)

Factors Influencing Intensity of Southwest Monsoons

Strengths of low pressure over the Tibetan plateau and high pressure present in the south Indian Ocean

1. Somali Jet
2. Somali Current
3. Indian Ocean Dipole
4. Indian Ocean branch of Walker cell

Two branches of Southwest Monsoon

The southwest monsoon arrives in two branches called the Bay of Bengal branch and the Arabian Sea branch. Arabian Sea side monsoon creates a low-pressure area on the Thar desert and is quite stronger in the Bay of Bengal side of the monsoon.

First Indian state receiving Southwest Monsoon

The Western Ghats of the coastal state of Kerala in India are first hit by the Arabian Sea branch of the southwest monsoon.

The reason why Southwest monsoon breaks into two branches

Southwest monsoon breaks into two branches because of topographic reasons. When the southwest monsoon hits the western ghats, it branches into two parts, the Arabian Sea branch, and the Bay of Bengal branch.

Why Tamil Nadu remains dry during Southwest Monsoon?

Tamil Nadu remains dry during southwest monsoon as it is located in the rain shadow area. Tamil Nadu receives rainfall in the winter season due to northeast trade winds.

Why Southwest Monsoon brings heavy rains?

The summer monsoon weather refers to a strong, generally west or southwest breeze which is responsible for bringing significant rainfall to the Asian subcontinent. The significant southwest monsoon is a by-product of air passing by large areas of the warm equatorial ocean, stimulating increased evaporation from the ocean surface, so the southwest monsoon air laden with water vapor cools as it moves north and also raises over land, no longer able to retain the moisture and falls down as rainfall, sometimes leading to severe type of flooding.

Northeast Monsoon

The northeast monsoon is caused by high-pressure cells over the Tibetan and Siberian Plateaus. The NE monsoon winds bring rainfall to the southeast coast of the country which includes the Tamil Nadu coast as well as Seemandhra’s south coast.

The factors which are mostly responsible for the formation of NE monsoons include:

1. Formation as well as strengths of high-pressure cells over Tibetan and also Siberian Plateaus during winters.
2. Migration of Inter Tropical Convergence Zone to the south of India.
3. High-pressure cells in the Southern Indian Ocean migrated to the west and then weakened.

Read More: 

1. Southwest Monsoon and Northeast Monsoon, 
2. Difference between Summer Monsoon and Retreating Monsoons.
3. Monsoon as Unifying Bond
4. Why South West Monsoons are less rainy in Chennai?

Monsoon of India

The Monsoon winds firmly impact the climate of India. The Arabs, who had additionally come to India as dealers named this occasional inversion of the wind framework ‘monsoon’. 

• Indian Monsoon is influenced by the presence of a great pressure region in East Madagascar roughly at  20°S over the Indian Ocean; influences the Indian Monsoon.
• At the point when the land is warmed and water bodies get cooled, it makes low tension on the ground and high strain over the ocean as well as the other way around.
• The shift of the place of the Inter-Tropical Assembly Zone in summer, over the Ganga plain (this is the tropical box typically situated around 5°N of the equator. It is otherwise called the monsoon.
• The inordinate warming of the Tibetan level during summer brings about solid air flows which are vertical in bearing.
• If the pressure contrasts were negative, it would mean underneath normal and late monsoon. A component associated with the SO is the El Nino phenomenon wherein a warm sea momentum streams past the Peruvian Coast.
• The changes in pressure conditions are associated with El Nino. Thus, the phenomenon is alluded to as ENSO (El Nino Southern Oscillations).

Read More: 

1. Monsoons in India
2. Characteristics and Effects of Monsoon in India
3. Characteristics of monsoon rainfall in India
4. Role of Western Disturbances in Indian Climate
5. Why Tamil Nadu coast achieve winter rainfall?

Onset and Withdrawal of Monsoon

The length of the rainstorm is between 100 and 120 days from early June to mid-September.  the typical precipitation expands out of nowhere and proceeds continually for a very long time. This is known as the ‘explosion’ Or  “burst” of the monsoon and can be recognized from the monsoon showers.

The Monsoon, in contrast to the exchanges, is not consistent twists yet is throbbing in nature, impacted by different climatic circumstances experienced by it.

Arrival Of Monsoon In Various Places In India

The monsoon shows up at the southern tip of the Indian promontory for the most part by the first seven-day stretch of June. In this way, it continues into two – the Arabian Sea branch and the Bay of Bengal branch.

• The Bay of Bengal branch shows up in Assam in the first seven-day stretch of June.
• By mid-June, the Arabian Sea port of the rainstorm shows up over Saurashtra-Kachchh and is the focal piece of the country.
• Western Uttar Pradesh, Punjab, Haryana, and eastern Rajasthan experience the monsoon, during the principal seven-day stretch of July.
• The Arabian Sea branch arrives in Mumbai on roughly the tenth of June.
• Delhi gets the monsoon showers from the Bay of Bengal branch before the finish of June.
• By mid-July, the storm arrives at Himachal Pradesh and the remainder of the country.
• The northwestern piece of the Ganga fields by the Arabian Sea and the Bay of Bengal parts of the monsoon converge.

Withdrawal Or The Retreat Of The Monsoon 

• The islands get the absolute first monsoon showers, dynamically from south to north, from the last seven-day stretch of April to the principal seven-day stretch of May. 
• The withdrawal happens dynamically from north to south from the primary seven-day stretch of December to the main seven-day stretch of January.
• By this time the remainder of the nation is now under the impact of the colder time of year monsoon. 
• The withdrawal of the rainstorm starts in northwestern provinces of India by right on time September. By mid-October, it pulls out totally from the northern portion of the landmass. 
• The withdrawal from the southern big part of the landmass is genuinely quick. By right on time
  December, the storm has removed from the remainder of the country.

There are two Seasons that are classified as Monsoons

1. Retreating/Post Monsoons (The Transition Season): In this season Monsoons become more fragile in the Northern area from mid-October to November. During the days, there is a climb in temperature and stickiness known as ‘October Heat’. The sky turns out to be clear and the temperature begins increasing. As a rule, it is more sultry during the day and the evenings are cooler. By mid-October, the temperature decreases quickly in North India.
2. Advancing Monsoon (The Rainy Season): In this season By early June, the low-pressure condition over the northern fields strengthens. It draws in, the exchange winds of the southern hemisphere. As these winds blow over warm seas, they bring abundant dampness to the subcontinent. These breezes are solid and blow at a normal speed of 30 km each hour. Except for the extreme northwest, the rainstorm winds cover the country for about a month.

FAQs on Monsoon in India

Q1. What causes a tropical cyclone?

Answer-

The summer monsoon season in India lasts from June to September, with a huge part of western as well as central India receiving more than 90 percent of their total annual precipitation during this period and south as well as northwestern India receiving 50 to 75 percent of total annual rainfall. The average is 200-300 mm over the country as a whole.

Q2. Which countries have monsoon seasons?

Answer-

 The summer monsoon is associated with heavy rainfall and happens between April and September. With the winter ending, moist air is blown from the southwest Indian Ocean towards countries like India, Sri Lanka, Bangladesh, and also Myanmar. The summer monsoon along with the winter monsoon determines the climate of most of India and also Southeast Asia.

Q3. What are the features of monsoon?

Answer-

The important features of monsoon include relief, which is erratic and also unpredictable. Sometimes the rainfall comes early and at other times they are uneven. Some regions received over 200 cm of rain and suffer from floods while others receive less than 50 cm annually and also experience semi-desert conditions.

Q4. What causes a monsoon?

Answer-

During summers, sunlight heats the surface of both lands and oceans, the land temperature rises more quickly because of lower heat capacity and as the surface becomes warmer, the air above it expands and an area of low pressure develops. At the same time, the ocean remains at a lower temperature than the land and so the air above it retains a higher pressure since the winds flow from areas of low, this deficit in pressure over the continent causes winds to blow from the ocean to land circulation and the wind blows from ocean to land, moist air is brought inland.

Q5. Which countries have the most monsoons?

Answer-

The region stretches from the south china sea into the Indian Ocean and includes Asia and also the northern part of Australia. From June to September, the summer monsoon occurs in many south Asian countries like Vietnam, Thailand, Cambodia, Bangladesh, Laos, India, and Pakistan.