INDIA - Climate
IMPACT OF CLIMATE
Climate is one of the most fundamental elements of our natural environment. Climate of an area influences human life in a variety of ways. You will notice that the climate in the mountainous regions of India is very cold. The people living there wear heavy woollen clothes all the year round. On the other hand, the people living in the southern parts of the Peninsular Plateau hardly need woollen garments. The climate affects not only the clothing habits of people but also many other aspects of their lives.
Climate determines the types of crops that can grow in an area. Can you think of growing coffee in the highest reaches of the Himalayas or wheat in the delta regions along the Bay of Bengal ? It cannot be done because the climatic requirements for the cultivation of a crop are not found in all parts of the country. The differences in crops grown in various parts of our country cause variations in the food habits of the people. Even the shapes and styles of the houses of the people are different in various parts of our country due to variation in climatic conditions. You will notice that the houses in the rainy and mountainous regions have sloping roofs while those in the dry and plain areas have flat roofs. Thus, all aspects of human life in an area are affected by the climatic conditions.
CLIMATE OF INDIA
The climate of India is described as the 'monsoon' type. This type of climate is found mainly in the south and the Southeast Asia. The climate of India is strongly influenced by monsoon winds. The term monsoon has been derived from the Arabic Mausam meaning season. Thus the monsoon are the seasonal winds which reverse their direction of flow with the change of season. They flow from sea to land during the summer and from land to sea during winter.
FACTORS AFFECTING THE CLIMATE OF INDIA
1. Latitude: India lies between 8°N and 37°N latitudes. The Tropic of Cancer passes through the middle of India. While the southern part lies in the tropical zone, the northern part falls in the sub-tropical zone. As such the temperature remains quite high during summer season all over the country except in the areas of high altitudes. But during winter, temperature falls considerably in the northern plains and records below freezing point in many parts of the Himala- yan belt. However, it is low to moderate in the rest of the country. Thus, India by and large enjoys a hot tropical climate.
2. The Himalayan Mountains: The Himalayas are also responsible for the tropical climate of India. This high and extensive mountain system protects India from the
cold winds of the north. At the same time, the Himalayas obstruct the southwesterly monsoon winds thereby causing heavy rainfall in the northern plains of India,
3. Distance from the Sea: The Peninsular character of southern India also has its climatic influence. With a long coastline, we have a large coastal area enjoying the equable influence of the sea. However, a large area in the northern part of the country lies too far away from the sea. Here the climate is continental.
4. Altitude Relief of land is also an important factor affecting the climatic conditions in various parts of India. A higher altitude is responsible for lower temperatures not only in the northern mountainous region but also in the Peninsular Plateau region.lon Hill stations of the Peninsular Plateau region, such as Ootacamund (Ooty), though quite close to the equator, have a rather cool climate. However, the temperatures in the Himalayan region are still lower due to both a greater distance from the equator and a higher altitude. That is why the hill stations are most numerous in the Himalayas. Find out the location of various important hill stations of India. On which range are they situated?
5. Conditions in the regions surroun- ding India Temperature and pressure conditions in East Africa, Iran, Central Asia and Tibet determine the strength of the monsoon and the occasional dry spells.
CYCLE OF SEASONS
There are four distinct seasons in India:
1. The Cold Weather Season.
2. The Hot Weather Season.
3. The Season of the Advancing Monsoon.
4. The Season of the Retreating Monsoon.
1. The Cold Weather Season (December. February):
(a) The cold weather season or winter begins in mid-November in north India. It gets well established all over the country by December and continues till February.
(b) However, the temperatures are not equally low at all places. While day temperature at places like Chennai is about 25° Celsius, at places like Amritsar it might be as low as 10 Celsius.
(c) During the winter season, parts of Punjab and Jammu and Kashmir get rain brought by Western Disturbances which originate in the Mediterranean sea. This rainfall is very beneficial for the wheat crop-patriotie
EQUABLE CLIMATE
1. The annual range of temperature is very low
2.. Summers are not very hot and winters are not very cold
2 Summers are very hot and winters are very cold.
3. Equable climate is found in the coastal and equatorial regions.
EXTREME CLIMATE
1. The annual range of temperature is very high
3. Extreme type of climate is found in the interior parts of the country. In India, north and northern-western parts experience an extreme type of climate.
(d) During this season the Coromandel coast region in Tamil Nadu also receives rainfall. These rains are caused by the north-east monsoon winds. The winds blowing from northeastern part of India pick up moisture while blowing over Bay of Bengal and cause rainfall after striking Tamil Nadu coast
2. The Hot Weather Season (March-May):
(a) This season begins in March and ends in May.
(b) Temperature begins to rise in March and the highest temperature is reached by the end of May and the beginning of June.
(c) The highest temperature is found in the northern plains (an average 30- 35°C) but the Deccan plateau is relatively cooler due to higher altitude.
(d) In the larger parts of the Ganga plains, the hot and dry winds called 'loo' are common during this season.
(e) Towards the close of summer premonsoon showers are a common phenomenon in Kerala and the coastal areas of Karnataka.
3. The Season of Advancing Monsoon (June-September):
(a) The hot dry season is followed by the rainy season or the season of the southwest monsoons. This season extends from June to September.
(b) The low pressure centre in the northwestern part of the country becomes more intense. This is due to the fact that the sun's rays during this season are vertical over the Tropic of Cancer. As a result of this low pressure centre over northern India, the southeastern trade winds blowing from the Tropic of Capricorn in the southern hemisphere are attracted to northern India.
(c) These winds blow over ocean and are thus moist. They extend over the Arabian Sea and the Bay of Bengal. Due to a comparatively lower pressure over land than the pressure over sea, they start blowing towards land. These winds are called the southwest monsoon winds..
Monsoon: A system of winds in which the direction of winds is completely reversed from one season to the other. A large part of Asia experiences this type of wind system.
South-west monsoon winds have tw branches the Arabian Sea brand (100-20 and the Bay of Bengal branch.
4. The Season of the Retreating Monsoor Mahare (October-November):
(a) After july the vertical rays of the sun start shifting towards the south and the temperature in the north starts declining. By October, the intensity of rainfall becomes very low and the southwest monsoon starts retreating gradually. The withdrawal of monsoon begins from the north and it withdraw from Punjab plains around mid September. By late October it withdraws from the Ganga delta. By early November the southwest monsoon withdraws completely from the peninsular region. This season is called the season of retreating monsoon.
(b) Weather in October is oppressive due to high temperature and high humidity. The high temperature in this month is often called the 'October Heat'.
DISTRIBUTION OF RAINFALL
In a large country like India accompanied with variations of relief, the distribution of rainfall cannot be uniform. The distribution of rainfall in our country is determined by direction of the rain-bearing winds and relief features.
The world's heaviest rainfall is recorded around Mawsynram near Cherrapunji in Meghalaya which is about 1,142 cm per annum.
1. Areas of heavy rainfall (over 200 cm of annual rainfall): The southern slopes of the eastern Himalayas, Assam, West Bengal and east coast receive heavy rainfall.
2. Areas of moderately heavy rainfall: (100-200 cm of annual rainfall): The middle Ganga valley, the Western Ghats, eastern southern plateaus of Karnataka, Andhra Pradesh and Tamil Nadu.
Maharashtra, Madhya Pradesh and Orissa.
3. Areas of moderate rainfall (50-100 cm of annual rainfall): The Upper Ganga valley, eastern Rajasthan and Punjab, of Kashmir, western Rajasthan and Punjab and Deccan Plateau (rain-shadow areas of the Western Ghats).
4. Areas of scanty rainfall (less than 50 cm of annual rainfall): Northern parts
Importance of the Monsoons:
1. The life of the Indian people including the agricultural activities revolves around the monsoons.
2. India is an agricultural land. Monsoon
plays important role in the agricultura production.
3. Despite climatic contrasts and variations from region to region, the monsoons provide a rhythmic cycle of seasons year after year.
RECAPITULATION
1. Climate is one of the most important elements of natural environment affecting the life of men in any region
2. Monsoon winds are the most important factor determining the climatic conditions in India.
3. The onset of the southwest monsoon begins in the month of June and it remains active over India till
September.
4. The southwest monsoon starts withdrawing from India in September and it is followed by the season of the northeast monsoon.
5. Most of the rainfall in India is received from the southwest monsoon in summer season. Only Tamil Nadu
receives some rain from the northeast monsoon in winter. 6. Another area where precipitation is received in winters is the northwestern part of the country which comes under the influence of the westerly depressions.