Welcome dear students! Today we are going to learn about India Seasons from Class 10 Social_Science. In this chapter, you will study the main features of India’s climate, the conditions of its climatic seasons, and the distribution of seasonal rainfall. India experiences a tropical monsoon type of climate. In this type of climate, winds blow in opposite directions in different seasons. During the first half of the year, the winds blow from South-West to North-East, and during the remaining half, they blow from North-East to South-West. The word Monsoon is derived from the Arabic word ‘Mausim’, which means seasons. Geographically, India is situated in both tropical and temperate zones. Factors such as latitude, height from sea level, distance from the sea, direction of winds, mountain ranges, and ocean currents influence the country's climate. The Indian climate is divided into four seasons: Summer season from March to May, South-west Monsoon season from June to September, Retreating monsoon season from October to November, and Winter season from December to February. [CHECKPOINT]
The summer season begins from the first week of March and continues till the end of May. During this season, the sun rays are perpendicular in the Northern hemisphere, causing high temperatures and long days. The North-Indian plains are away from the sea and experience very high temperatures. Ganganagar of Rajasthan records a maximum of 52°C in summer, making it the hottest place in the country. In contrast, South India is surrounded by water on three sides, so the temperature is moderate, ranging between 32°C to 35°C. The North-Indian mountain regions and the peninsular plateau remain cooler. Due to local temperature and convection currents, rainfall occurs in some places during April and May. This is called convectional rainfall. These showers are known as ‘Kala Baisakhi’ in West Bengal, ‘Andhis’ in Uttar Pradesh, ‘Coffee blossoms’ in Karnataka, and ‘Mango showers’ in Kerala. During summer, the country receives only 10% of its annual rainfall. [CHECKPOINT]
The South-West Monsoon comprises the rainy season in India, spreading from June to September. These winds are very humid and shower rain over most parts of the country, accounting for 75% of the annual rainfall. The South-West Monsoon separates into two branches: the Arabian Sea branch and the Bay of Bengal branch. The monsoon winds are obstructed by the Western Ghats, causing maximum rainfall to the west of the Ghats. As the winds move eastward, they get depleted of moisture, making the eastern regions of the Western Ghats rain-shadow regions. The Bay of Bengal monsoon winds bring rain to Myanmar, Bangladesh, North-East Indian regions, the foothills of the Himalayas, and the North-Indian plains. Rainfall reduces as we move from North-East to North-West. Except for the Tamil Nadu region, most of the country receives rain during the South-West Monsoon. [CHECKPOINT]
By the end of October, due to widespread South-West Monsoon rains, temperatures decrease. During this season, sun rays fall vertically on the Southern hemisphere, causing a temperature drop in the Northern hemisphere. This area becomes a high-pressure zone, and the South-West monsoon winds start receding, stopping completely by the end of November. This is called the Receding Monsoon Period or North-East monsoon period. India receives about 13% of annual rainfall during this season due to differences in temperature and pressure between land and sea. Tropical cyclones frequently occur in the Bay of Bengal during this season, causing widespread damage along their path, particularly along the coast. The winter season begins in December and ends in February. Ladakh, Jammu and Kashmir, Himachal Pradesh, and the North-Indian plains witness very low temperatures, sometimes dropping to sub-zero levels with heavy snowfall. In South India, the temperature is normal and the climate is pleasant. India receives just 2% of annual rainfall in winter, making it the season of least rainfall. [CHECKPOINT]
Rainfall distribution in India shows significant variation. The country’s average annual rainfall is 118 cm. Based on total rainfall, India is divided into three regions. First, the low rainfall region receives less than 50 cm. These deficit areas include the Thar desert of Rajasthan, adjoining areas like Punjab, Haryana, the Kachchh region of Gujarat, Ladakh, Jammu and Kashmir, eastern parts of Maharashtra, and interior Karnataka. Ruyli of Jaisalmer district in Rajasthan receives the least annual rainfall of 8.3 cm in the country. Second, the moderate rainfall region receives between 50 to 250 cm, covering all areas not classified as low or surplus. Third, the heavy rainfall region receives more than 250 cm, including the western areas of the Western Ghats, Assam, other eastern states, and West Bengal. The Mawsynram region of Meghalaya gets the highest rainfall in the country. [CHECKPOINT]
Climatic conditions greatly influence the economy. The South-West monsoon controls Indian agriculture, the main occupation of the people. Failure of rainfall leads to drought, while heavy monsoons cause floods that destroy life and property. Hence, Indian agriculture is called a “gamble with the monsoons.” Now, let us review the activities and exercises. First activity: Collect information from newspapers about the temperature in major cities and discuss the variation in temperature with your teacher. Second activity: Find out the amount of rainfall received in your taluk this year and discuss the climatic conditions with your friends. Now, review the exercises. Fill in the blanks: One, the highest temperature region in the country is Ganganagar of Rajasthan. Two, due to local temperature and convection currents, convectional rainfall occurs. Three, the area receiving very less rainfall in our country is Ruyli of Jaisalmer district in Rajasthan. Four, the area receiving the highest rainfall in our country is the Mawsynram region of Meghalaya. [CHECKPOINT]
Answer the following questions briefly. Five, India experiences a tropical monsoon type of climate. Six, cyclonic winds occur during the withdrawal of monsoons due to differences in temperature and pressure between land and sea, frequently forming in the Bay of Bengal. Seven, factors influencing India's climate include latitude, height from sea level, distance from the sea, direction of winds, mountain ranges, and ocean currents. Eight, Indian agriculture is a “gamble with the monsoons” because crop success depends entirely on monsoon timing and intensity; failure causes drought, while excess causes floods, both leading to severe economic and property loss. Match the following: Column A lists Kala Baisakhi, Andhis, Coffee blossom, and Mango showers. Column B lists Uttar Pradesh, Karnataka, Kerala, Rajasthan, and West Bengal. The correct matches are: Kala Baisakhi corresponds to West Bengal, Andhis corresponds to Uttar Pradesh, Coffee blossom corresponds to Karnataka, and Mango showers corresponds to Kerala. Rajasthan is an extra option in Column B. Activity: Draw a map of India and mark the distribution of rainfall. Project: Learn from your teachers about the seasonal characteristics in your area. Thank you for listening! Keep revising and practicing. Goodbye! [CHAPTER_COMPLETE]