1442 words essay on the climate of India

The Tropic of Cancer divides India almost into two equal parts; so the north India comes under the Warm Temperate Zone whereas the south India under the Tropical Zone. The cold north-wind can’t enter into India owing to the situation of the Himalayas in the north. So India is a tropical country. Its climate is very much influenced by its vastness, location, variation in physiographic, extension of the sea and the monsoon winds.

The monsoons are an occasional wind. It does not blow from a definite direction throughout the year. The direction of wind changes with the change of seasons. The inland distribution of temperature and pressure conditions of interior India control the direction of wind. Variation in rainfall is caused owing to the monsoon winds in different regions of India.

In the opinion of the meteorologists the monsoon winds primarily influence the climate of India. Therefore, the climate of India is generally said to be the monsoon-climate.

South-west monsoons:

The sun gives direct rays on the Tropic of Cancer in the month of June. So low pressure is caused owing to intense heat in the north-western region of India. During that time high pressure is caused in the Indian Ocean. So the wind blows from the high pressure area over the Indian Ocean to the low pressure area over the landmass of the country. As such, from over the Indian Ocean on the south of the equator the South-East Trade Wind blows crossing the equator and as per the Ferrets Law this wind deflects to the right after crossing the equator.

So to say, the South-East Trade Wind after crossing the equator blows as the South-West Monsoons towards the inland low pres­sure area. The monsoons reach on 5th June in Maharashtra, on 15th June in West Bengal, on 25th June in Uttar Pradesh and on 1st July in the State of Punjab. Hence the effects of the monsoons are felt from the beginning of June in the Andaman and Nicobar Islands., Lakshadweep and the Malabar coast of south India and this wind spreads all over India by the first week of July.

This warm wind absorbs ample moisture from the surface of the sea as it passes over hundreds of kilometers of long oceanic path. Under its influence, widespread rainfall is caused in most of the regions of India except the Coromondal Coast. This wind blows over India from June to September. Before entering into India this wind is divided into two branches via; the Arabian Sea branch and the Bay of Bengal’ branch owing to the shape of the Indian Peninsula.

The Arabian Sea branch that blows over the Arabian Sea passes over Lakshadweep and enters into the landmass near the Malabar Coast. It is intercepted by the Western Ghats and so goes upwards and is cooled up. The moisture-laden wind is condensed causing heavy downpour in the west of the Western Ghats and in the western coastal plains.

The amount of moisture lessens as the wind, having crossed the Western Ghats, proceeds towards the Deccan Plateau. Its temperature also increases as it descends. So the process of condensation slows down and hence, the amount of rainfall gradually decreases. For example, the amount of rainfall at Mangalore is 250 cms between June to September whereas it is only 50 cms at Bangalore during that period.

Some narrow sub-branches of the Arabian Sea branch of monsoons pass through the Pal hat Pass and the Narmada and Tapti Valleys and having blown over the middle of the peninsular India, proceed towards the east. This wind being intercepted by the Ravalli, Vindhyas and the Sapura ranges, gives some amount of rainfall in the northern part of the Deccan Plateau. Another sub-branch of these monsoons passes over the north-western part of India and Rajasthan. But as its temperature increases and having no natural barrier like high mountain ranges in its path, this region gets scanty rainfall from this wind. So, the Tharp or the Great Indian Desert is created.

The branch of monsoon that blows over the Bay of Bengal proceeds being almost parallel with the East Coast, towards the north-eastern direction i.e. towards the mountainous areas of Assam and Meghalaya. At this time a number of whirlpools or cyclones are created over the Andaman and Nicobar Islands. Those cyclones advance mainly towards north-west and proceed towards the Chhotnagpur Plateau along the coast of Belabored of Orissa. These cyclones cause heavy rainfall in the east coast of Orissa.

Another branch of this monsoon blows to­wards north and enters into the Gangetic delta and the Shilling Plateau area. It enters there into a funnel shaped narrow valley formed by the Agro, Khaki, Naga and Shilling ranges and the Lucia ranges ex­tending north-south wise. This wind being shot up condenses profusely and rains heavily. Cherapunji, situated in this area gets the highest rainfall in the world the annual average rainfall being about 1250 comes.

But Shilling situated in the lee-ward side (or, the rain shadow area of the Shilling Plateau gets an annual average rainfall of only 200 comes. even though it is at a distance of only 40 kms. from Cherapunji. These motions cannot cross the Himalayas. So it moves along the foot Himalayas towards the low • pressure centre created in the Punjab Plains. As a result of this rainfall is caused in West Bengal, Bihar, Uttar Pradesh, Himachal Pradesh, Haryana and Punjab. Since the moisture contained in the wind gradually lessens, the amount of rainfall decreases along with it from West Bengal to Punjab.

The monsoons get weaker towards the end of September, and, as such, the amount of rainfall also decreases. In this manner, both the Arabian Sea and the Bay of Bengal branches of the monsoons cause rainfall in the interior regions of India.

Retreating south-west monsoons:

The sun moves towards the south after the 23rd September. So the direct rays of the sun fall on the Indian Ocean on the south of the equator. It causes a comparatively low pressure area there. The landmass of the north India gradually gets cooler and creates high pressure of air. So at this time, the monsoons over the north Indian plains change their direction and move southwards retreating over the Bay of Bengal and the Arabian Sea. This is called the ‘Retreating South West Monsoon’, which causes slight rainfall in the Gang etic Plains, Orissa and coastal Andhra Pradesh regions. But it causes heavy rainfall in the Coromandal Coasts of Tamilnadu. When the rainy season gradually comes to an end in other regions of India, it almost sets in, in the coastal Tamilnadu by this time. The summer monsoons gradually retreat and come to a close by the end of November and the winter North-East Monsoon is felt.

North-east monsoons:

This wind generally blows from December to March over the landmass of India towards the low pressure area of the Indian Ocean on the south. It is almost a dry wind as it blows over the landmass. But it absorbs a little amount of moisture while blowing over the Bay of Bengal. So it gives a good amount of rainfall while crossing along the Coromandal Coast of Tamilnadu. Thus Tamilnadu coast enjoys two rainy seasons during the year.

Sometimes severe cold is felt in north India because of cold waves caused by the North-East Monsoon. It also causes rainfall to some extent in the foot of Himalayan region from Kashmir to the western part of Uttar Pradesh. This rainfall helps very much in cultivation of wheat in north India. Again the temperature rises in most parts of India in the later part of March. Owing to the northward motion of the sun, severe heat is felt in the plains of north India. Severe cyclones are caused in the Arabian Sea and the Bay of Bengal in the months of April and May.

Occasionally severe types of storms occur in the summer afternoons of the month of Baisakh in Assam, West Bengal and the northern parts of Orissa. Such type of storm is known as “Kal Baisakhi.” The rainfall caused by this “Kal Baisakhr helps a lot in cultivation of jute and tea in this region. During this time, a hot sand storm called “Loo” blows over Rajasthan and proceeds towards the Gang etic Valley up to the western parts of Uttar Pradesh. It sometimes hinders the flights of aero planes.

In India a year is divided into six seasons, such as summer, rainy, autumn, dewy, winter and spring. But on the basis of annual distribution of temperature and rainfall, mainly four seasons are felt in India, such as: summer, rainy, autumn and winter.