Part A – Multiple Choice Questions (MCQs)
Q1. Which of the following controls the climate of a place the most?
(a) Latitude
(b) Altitude
(c) Ocean currents
(d) All of these
Ans: (d) All of these
Q2. What is the average weather condition over a long period called?
(a) Climate
(b) Weather
(c) Season
(d) Monsoon
Ans: (a) Climate
Q3. The monsoon winds blow from:
(a) Land to sea in summer
(b) Sea to land in summer
(c) Sea to sea
(d) None of these
Ans: (b) Sea to land in summer
Q4. Which two branches does the southwest monsoon divide into?
(a) Arabian Sea and Bay of Bengal branch
(b) Western Ghats and Himalayas branch
(c) North and South branch
(d) East and West branch
Ans: (a) Arabian Sea and Bay of Bengal branch
Q5. The normal lapse rate of temperature with altitude is:
(a) 1°C per 100 m
(b) 6.5°C per 1000 m
(c) 10°C per 500 m
(d) 5°C per 200 m
Ans: (b) 6.5°C per 1000 m
Q6. Which winds are responsible for rainfall in winter in northwestern India?
(a) Southwest monsoon
(b) Northeast trade winds
(c) Western disturbances
(d) Jet streams
Ans: (c) Western disturbances
Q7. The Indian monsoon is:
(a) Hot and dry
(b) Seasonal reversal of wind
(c) Local wind system
(d) Permanent wind
Ans: (b) Seasonal reversal of wind
Q8. Which place in India receives the highest annual rainfall?
(a) Mawsynram
(b) Cherrapunji
(c) Agartala
(d) Shillong
Ans: (a) Mawsynram
Q9. Which season is known as the retreating monsoon in India?
(a) Summer
(b) Winter
(c) October–November
(d) March–April
Ans: (c) October–November
Q10. Which is the coldest month in India?
(a) October
(b) December
(c) January
(d) February
Ans: (c) January
Q11. The pressure and wind system of any area depends on:
(a) Latitude
(b) Altitude
(c) Temperature
(d) All of these
Ans: (d) All of these
Q12. The burst of the monsoon in India takes place in:
(a) July
(b) August
(c) June
(d) May
Ans: (c) June
Q13. Which part of India receives rainfall in winter?
(a) Kerala
(b) Rajasthan
(c) Tamil Nadu coast
(d) Gujarat
Ans: (c) Tamil Nadu coast
Q14. Monsoon rainfall is largely:
(a) Evenly distributed
(b) Seasonal and uncertain
(c) Daily and regular
(d) Predictable and uniform
Ans: (b) Seasonal and uncertain
Q15. The word “Monsoon” is derived from:
(a) Arabic
(b) Hindi
(c) Sanskrit
(d) Persian
Ans: (a) Arabic
Q16. Which factor brings the monsoon to India?
(a) Jet streams
(b) ITCZ shift northward
(c) Ocean currents
(d) Local winds
Ans: (b) ITCZ shift northward
Q17. The Coriolis force is generated due to:
(a) Earth’s rotation
(b) Earth’s revolution
(c) Earth’s tilt
(d) Gravitational pull
Ans: (a) Earth’s rotation
Q18. The monsoon winds retreat when:
(a) Land gets colder than sea
(b) Sea gets colder than land
(c) Summer sets in
(d) ITCZ moves north
Ans: (a) Land gets colder than sea
Q19. Jet streams are located in which layer of the atmosphere?
(a) Troposphere
(b) Stratosphere
(c) Mesosphere
(d) Ionosphere
Ans: (a) Troposphere
Q20. Mango showers occur in:
(a) Kerala
(b) Tamil Nadu
(c) Karnataka and Kerala
(d) Maharashtra
Ans: (c) Karnataka and Kerala
Part B – Assertion and Reason Questions
Each has 4 options:
(A) Both A and R are true and R is the correct explanation of A.
(B) Both A and R are true but R is not the correct explanation of A.
(C) A is true but R is false.
(D) A is false but R is true.
Q1.
Assertion (A): The climate of India is described as monsoon type.
Reason (R): India experiences seasonal reversal of winds.
Ans: (A)
Q2.
Assertion (A): Mawsynram receives the highest rainfall in the world.
Reason (R): The Bay of Bengal branch of the monsoon is trapped by the Khasi Hills.
Ans: (A)
Q3.
Assertion (A): The Indian monsoon is highly predictable.
Reason (R): Monsoon winds blow regularly every year with the same intensity.
Ans: (C)
Q4.
Assertion (A): Tamil Nadu coast gets rainfall in winter.
Reason (R): Northeast monsoon winds pick moisture from the Bay of Bengal.
Ans: (A)
Q5.
Assertion (A): The southwest monsoon arrives in India in June.
Reason (R): ITCZ shifts northwards in summer.
Ans: (A)
Q6.
Assertion (A): The western disturbances cause rainfall in northwestern India.
Reason (R): They are moisture-laden winds from the Mediterranean Sea.
Ans: (A)
Q7.
Assertion (A): The Coriolis force affects the direction of winds.
Reason (R): It arises due to the Earth’s rotation.
Ans: (A)
Q8.
Assertion (A): Jet streams influence the onset and retreat of monsoon.
Reason (R): They affect air circulation patterns over the Indian subcontinent.
Ans: (A)
Q9.
Assertion (A): Retreating monsoon brings clear skies and rise in temperature.
Reason (R): Winds blow from land to sea during this period.
Ans: (A)
Q10.
Assertion (A): Rainfall in India is evenly distributed.
Reason (R): Monsoon winds cover the entire country uniformly.
Ans: (D)
Q11.
Assertion (A): Mango showers are beneficial for coffee plantations.
Reason (R): They occur in Karnataka and Kerala during pre-monsoon season.
Ans: (A)
Q12.
Assertion (A): Monsoon winds are influenced by differential heating of land and sea.
Reason (R): Land heats up faster than water in summer.
Ans: (A)
Q13.
Assertion (A): India has a wide variety of climatic conditions.
Reason (R): India has diverse relief features and location influences.
Ans: (A)
Q14.
Assertion (A): The Himalayas play a role in the Indian climate.
Reason (R): They act as a barrier to cold winds from Central Asia.
Ans: (A)
Q15.
Assertion (A): The monsoon is a unifying bond in India.
Reason (R): It influences agriculture, festivals, and lifestyle of people.
Ans: (A)
Q16.
Assertion (A): Rajasthan receives scanty rainfall.
Reason (R): The Aravalli range lies parallel to monsoon winds, offering no obstruction.
Ans: (A)
Q17.
Assertion (A): The Bay of Bengal branch of monsoon is stronger than the Arabian Sea branch.
Reason (R): It carries more moisture and covers a larger area.
Ans: (A)
Q18.
Assertion (A): October heat is felt during retreating monsoon.
Reason (R): The clear skies and high temperature increase humidity.
Ans: (A)
Q19.
Assertion (A): Coastal areas experience equable climate.
Reason (R): The sea moderates the temperature of coastal regions.
Ans: (A)
Q20.
Assertion (A): Monsoon winds are permanent winds.
Reason (R): They blow throughout the year in the same direction.
Ans: (D)
Part C – Very Short Answer
Q1. Define climate.
Ans: Climate refers to the average weather condition of a place observed over a long period of time, generally 30 to 35 years, including factors like temperature, rainfall, humidity, and winds.
Q2. Differentiate between weather and climate.
Ans: Weather is the short-term condition of the atmosphere at a given time and place, while climate is the average atmospheric condition over a longer period of time.
Q3. Why does India have a monsoon type of climate?
Ans: India experiences seasonal reversal of winds due to differential heating of land and sea and shifting of ITCZ, which makes its climate monsoon type.
Q4. What is ITCZ?
Ans: The Inter Tropical Convergence Zone (ITCZ) is a low-pressure zone near the equator where northeast and southeast trade winds converge, shifting north and south with seasons.
Q5. What is meant by the “burst” of monsoon?
Ans: The sudden onset of monsoon in June, bringing heavy downpour and thunderstorms after the hot summer season, is called the burst of the monsoon.
Q6. Name the two branches of the southwest monsoon.
Ans: The two branches of the southwest monsoon are:
- The Arabian Sea branch
- The Bay of Bengal branch.
Q7. Why does Mawsynram receive the highest rainfall?
Ans: Mawsynram receives the highest rainfall because the Bay of Bengal branch of the monsoon is trapped by the Khasi Hills, forcing the winds to rise and shed heavy rainfall.
Q8. What are western disturbances?
Ans: Western disturbances are moisture-laden winds originating in the Mediterranean Sea that bring winter rainfall in northwestern India, including Punjab, Haryana, and Delhi.
Q9. Why does Tamil Nadu receive rainfall in winter?
Ans: Tamil Nadu receives rainfall in winter because the northeast monsoon winds pick up moisture from the Bay of Bengal and cause rainfall along the Tamil Nadu coast.
Q10. What are jet streams?
Ans: Jet streams are narrow bands of high-speed winds in the upper troposphere that influence the onset and retreat of the Indian monsoon.
Q11. Which is the coldest month in India?
Ans: January is the coldest month in India as temperatures fall due to low sun angle and cold winds from northern regions.
Q12. What is October heat?
Ans: October heat refers to the hot and humid weather experienced in October due to retreating monsoon, clear skies, and rising temperatures.
Q13. Why does Rajasthan receive scanty rainfall?
Ans: Rajasthan receives scanty rainfall because the Aravalli Hills run parallel to the southwest monsoon winds, offering no barrier to intercept moisture-laden winds.
Q14. What are Mango showers?
Ans: Mango showers are pre-monsoon rains in Karnataka and Kerala that help in the early ripening of mangoes and benefit coffee plantations.
Q15. Why do coastal areas have equable climate?
Ans: Coastal areas have equable climate because the sea moderates temperature, keeping summers cooler and winters warmer compared to inland regions.
Q16. State one role of the Himalayas in India’s climate.
Ans: The Himalayas act as a barrier against cold winds from Central Asia, preventing India from experiencing extremely cold winters like Siberia.
Q17. Name the seasons into which the Indian climate has been divided.
Ans: The Indian climate is divided into four main seasons:
- Cold weather season (Winter)
- Hot weather season (Summer)
- Southwest monsoon season (Rainy)
- Retreating monsoon season.
Q18. Why is the monsoon considered a unifying bond in India?
Ans: The monsoon provides water for agriculture, influences festivals, lifestyle, and economy, making it a common factor that unites the entire country.
Q19. Why is the Indian monsoon uncertain?
Ans: The Indian monsoon is uncertain because its arrival, departure, and amount of rainfall vary every year due to complex global factors like El Niño and La Niña.
Q20. What is the normal lapse rate of temperature with altitude?
Ans: The normal lapse rate is 6.5°C decrease in temperature for every 1000 metres increase in altitude.
Part D – Short Answer
Q1. What are the major controls of the climate of India?
Ans: The major controls of India’s climate are latitude, altitude, pressure and wind system, distance from the sea, ocean currents, and relief features. For example, the Himalayas block cold winds from Central Asia, while the Thar Desert influences monsoon winds. Together, these factors shape India’s monsoon type climate.
Q2. Differentiate between climate and weather with examples.
Ans: Weather refers to short-term atmospheric conditions such as temperature, rainfall, and humidity at a given place and time. For example, it may rain in Delhi today. Climate is the average weather condition over a long period, like India’s climate being described as monsoon type due to seasonal reversal of winds.
Q3. Explain the role of latitude in influencing the climate of India.
Ans: India’s climate varies with latitude because the Tropic of Cancer passes through the middle of the country. Areas north of it have a continental climate with extreme summers and winters, while southern areas near the equator have a tropical climate with moderate temperature and more humidity due to sea proximity.
Q4. What is the ITCZ and how does it affect the Indian monsoon?
Ans: The Inter Tropical Convergence Zone (ITCZ) is a low-pressure zone near the equator where trade winds converge. In summer, it shifts northwards over the Indian subcontinent, drawing in moisture-laden southwest monsoon winds from the Indian Ocean, causing widespread rainfall across the country.
Q5. Why does the burst of monsoon occur suddenly?
Ans: The burst of monsoon occurs in June when southwest monsoon winds strike the Kerala coast, bringing heavy rain and thunderstorms after hot summers. The sudden shift from dry, scorching heat to heavy downpour gives it the term “burst,” marking the real beginning of India’s rainy season.
Q6. Explain the role of jet streams in the Indian climate.
Ans: Jet streams are high-speed winds in the upper troposphere. The westerly jet stream brings western disturbances in winter, causing rainfall in northwestern India. The easterly jet stream over peninsular India influences the onset and retreat of monsoon by guiding monsoon winds and their seasonal reversal.
Q7. Why does Mawsynram receive the highest rainfall in the world?
Ans: Mawsynram receives the world’s highest rainfall because the Bay of Bengal branch of the monsoon is trapped by the Khasi Hills in Meghalaya. These hills force the moisture-laden winds to rise and cool, causing extremely heavy and prolonged rainfall, making Mawsynram the wettest place on Earth.
Q8. What are western disturbances? How do they affect India?
Ans: Western disturbances are cyclonic systems originating in the Mediterranean Sea, carried by westerly jet streams. They cause winter rainfall in northwestern India, including Punjab, Haryana, and Delhi. This rainfall is crucial for wheat and rabi crops, though sometimes it also leads to hailstorms and crop damage.
Q9. Why does Tamil Nadu coast receive rainfall in winter?
Ans: Tamil Nadu coast receives rainfall in winter because the northeast monsoon winds blow from land to sea but pick up moisture from the Bay of Bengal. This moisture-laden wind strikes the eastern coast of Tamil Nadu, bringing rainfall during October to December.
Q10. Explain the phenomenon of October heat.
Ans: October heat occurs after the withdrawal of the southwest monsoon. During this time, skies become clear and temperatures rise, leading to hot and humid weather. The high humidity combined with rising day temperatures creates discomfort, especially in northern and central India, until winter sets in.
Q11. How do the Himalayas influence India’s climate?
Ans: The Himalayas act as a barrier against the icy cold winds from Central Asia, preventing extremely cold winters in northern India. They also obstruct the southwest monsoon winds, forcing them to shed moisture in the form of rainfall, thus shaping India’s climate and agricultural patterns.
Q12. Why does Rajasthan receive scanty rainfall?
Ans: Rajasthan receives scanty rainfall because the Aravalli Hills run parallel to the direction of the southwest monsoon winds. Hence, they do not obstruct the winds. Also, Rajasthan lies in the rain-shadow region, and the dry continental winds increase aridity, making the region semi-arid to arid.
Q13. What are Mango showers? How are they useful?
Ans: Mango showers are pre-monsoon rains occurring in Karnataka and Kerala during April and May. These rains help in the early ripening of mangoes, hence the name. They also benefit coffee plantations and prepare the soil for the upcoming southwest monsoon season.
Q14. Mention any three features of the hot weather season in India.
Ans: The hot weather season lasts from March to May. Temperatures rise steadily, with the northwestern parts experiencing loo (hot dry winds). Localised storms such as Kalbaisakhi in Bengal and mango showers in Kerala occur during this season, providing relief from heat.
Q15. Give reasons why coastal areas have equable climate.
Ans: Coastal areas have equable climate because the sea moderates the temperature. Water heats and cools more slowly than land. Therefore, coastal regions like Mumbai and Chennai have cooler summers and milder winters, unlike interior regions which experience extreme climatic conditions.
Q16. How is the monsoon a unifying bond for India?
Ans: The monsoon unites India by influencing agriculture, economy, lifestyle, and festivals. Farmers across the country depend on monsoon rains for crops. Cultural activities and festivals often coincide with the arrival or retreat of monsoon, making it a shared national experience.
Q17. Explain why the Indian monsoon is considered uncertain.
Ans: The Indian monsoon is uncertain because its arrival and departure dates, distribution, and total amount of rainfall vary each year. Factors like El Niño, La Niña, and local relief influence monsoon behaviour, leading to floods in some areas and droughts in others.
Q18. Write three characteristics of retreating monsoon.
Ans: The retreating monsoon lasts from October to November. It is marked by clear skies, high temperature, and humidity. The Tamil Nadu coast receives rainfall from northeast monsoon winds. This season is also known as October heat due to its uncomfortable weather.
Q19. State three factors that affect the temperature of India.
Ans: Temperature in India is affected by:
- Latitude – areas near the Tropic of Cancer experience extremes.
- Altitude – higher areas like Himachal Pradesh are cooler.
- Distance from the sea – coastal areas like Mumbai have moderate temperatures, while interiors like Delhi experience extremes.
Q20. What is the significance of monsoon rainfall in India?
Ans: Monsoon rainfall is vital for agriculture, which is the backbone of India’s economy. About 64% of cultivated land depends on rain. It replenishes groundwater, supports industries like power generation, and influences social and cultural life through festivals and seasonal activities.
Part E – Long Answer
Q1. Describe the factors that control the climate of India.
Ans: The climate of India is influenced by six major factors: Latitude, which determines the angle of the sun’s rays; Altitude, as higher regions like Himachal Pradesh remain cooler; Pressure and wind systems, which influence seasonal winds; Distance from the sea, where coastal areas like Mumbai experience equable climate while interiors like Delhi face extremes; Ocean currents, such as warm Gulf Stream and cold Labrador Current influencing coastal temperatures; and Relief features, like the Himalayas blocking cold Central Asian winds and forcing monsoon winds to shed moisture. Together, these factors give India its distinct monsoon type of climate.
Q2. Distinguish between weather and climate with examples.
Ans: Weather refers to the short-term condition of the atmosphere at a given place and time, such as temperature, rainfall, humidity, or wind. For example, Delhi may experience rain today but be dry tomorrow. Climate, on the other hand, is the long-term average weather pattern observed over at least 30–35 years. For instance, India’s climate is described as “monsoon type” because of seasonal reversal of winds. While weather changes frequently and can be unpredictable, climate is relatively stable and provides the background against which daily weather fluctuations occur. Thus, weather is temporary, but climate is permanent and long-term.
Q3. Explain the role of latitude, altitude, and distance from the sea in affecting India’s climate.
Ans: Latitude affects climate as the Tropic of Cancer passes through India. Areas north of it have a continental climate with extreme summers and winters, while southern areas experience a tropical climate. Altitude influences temperature since places at higher elevations, like Shimla, are cooler compared to Delhi at the same latitude. Distance from the sea affects temperature variations: coastal areas like Mumbai and Chennai have equable climate due to the moderating effect of the sea, while interiors like Jaipur and Delhi have extreme summers and winters. These three factors together create climatic diversity in India, ranging from arid deserts to humid coastal regions.
Q4. What is ITCZ? Explain its role in the Indian monsoon.
Ans: The Inter Tropical Convergence Zone (ITCZ) is a low-pressure belt located near the equator where trade winds from both hemispheres converge. Its position shifts with the sun. In summer, the ITCZ shifts northwards over the Indian subcontinent. This attracts moisture-laden southwest monsoon winds from the Indian Ocean, Arabian Sea, and Bay of Bengal, causing widespread rainfall in India. The seasonal migration of the ITCZ is a major factor responsible for the onset and distribution of monsoon rains. Its northward shift marks the rainy season, while its southward movement signals the retreat of the monsoon. Thus, the ITCZ plays a central role in India’s climatic cycle.
Q5. Explain the arrival and “burst” of the southwest monsoon in India.
Ans: The southwest monsoon arrives in India by the first week of June, striking the Kerala coast. Within a month, it covers most of the country. The “burst of monsoon” refers to the sudden onset of heavy rains accompanied by thunder and lightning after the hot, dry summer. The shift is dramatic as dry, scorching conditions give way to heavy downpour. The monsoon divides into two branches: the Arabian Sea branch, which brings rain to western coastal areas, and the Bay of Bengal branch, which moves towards northeast India and the Gangetic plains. The burst of monsoon marks the real beginning of India’s rainy season, crucial for agriculture.
Q6. Describe the role of jet streams in influencing India’s climate.
Ans: Jet streams are fast-moving air currents in the upper troposphere. The westerly jet stream, flowing over north India, is responsible for bringing western disturbances that cause winter rainfall in Punjab, Haryana, and northern plains. This rainfall is vital for rabi crops like wheat. The easterly jet stream, located over peninsular India, influences the advance and retreat of monsoon. During summer, the easterly jet guides the southwest monsoon winds towards the subcontinent. In winter, its shift contributes to dry conditions in most parts. Thus, jet streams act as invisible drivers of India’s weather systems, controlling rainfall patterns and temperature variations.
Q7. Why does Mawsynram receive the highest rainfall in the world? Explain.
Ans: Mawsynram, located in Meghalaya, receives the highest annual rainfall in the world due to its unique location and relief features. The Bay of Bengal branch of the southwest monsoon carries enormous moisture. When it reaches the Khasi Hills, the winds are trapped and forced to rise. As the air ascends, it cools and sheds heavy rainfall. The funnel-shaped relief of the hills further concentrates the rainfall in Mawsynram. Annual rainfall often exceeds 11,000 mm, making it the wettest place on Earth. The combination of moisture-laden winds and orographic effect makes Mawsynram a hotspot of global rainfall.
Q8. Explain the significance of western disturbances in India’s climate.
Ans: Western disturbances are cyclonic systems originating in the Mediterranean Sea. Carried by the westerly jet stream, they reach northwestern India during winter. They bring light to moderate rainfall in Punjab, Haryana, Delhi, and western Uttar Pradesh, and snowfall in the western Himalayas. This winter rainfall is crucial for rabi crops, especially wheat. However, sometimes they also cause hailstorms that damage crops. Without western disturbances, northern India would receive almost no winter rainfall, affecting food security. Hence, western disturbances play a critical role in balancing India’s agricultural calendar and maintaining climatic diversity in northwestern India.
Q9. Why does Tamil Nadu coast receive rainfall in winter? Explain.
Ans: Tamil Nadu coast receives rainfall in winter due to the retreating northeast monsoon. These winds blow from land to sea but pick up moisture from the Bay of Bengal. When they strike the Coromandel Coast of Tamil Nadu, they bring rainfall during October to December. This makes Tamil Nadu different from other states, as it receives most of its annual rainfall in winter rather than summer. This rainfall is vital for agriculture in Tamil Nadu, especially for paddy cultivation, and helps recharge water bodies before the dry season. Thus, the northeast monsoon is essential for the state’s economy and life.
Q10. What is October heat? Why is it experienced in India?
Ans: October heat refers to the hot and humid weather experienced after the retreat of the southwest monsoon. During this period, skies become clear, and temperatures rise sharply due to strong sunlight. However, the humidity remains high because of moisture left behind by retreating monsoon winds. This combination creates oppressive conditions in northern and central India. October heat continues until winter sets in by November. It is particularly uncomfortable in areas like West Bengal and Odisha, where cyclonic depressions from the Bay of Bengal also occur during this time. Hence, October heat is a distinct climatic feature of India’s retreating monsoon season.
Q11. How do the Himalayas affect the climate of India?
Ans: The Himalayas play a decisive role in India’s climate. They act as a barrier to cold winds from Central Asia, preventing northern India from experiencing extreme Siberian cold. They also obstruct moisture-laden southwest monsoon winds, forcing them to rise and cause heavy rainfall across northern plains and the northeast. The Himalayas are responsible for the diversity of rainfall and temperature across the subcontinent. They also cause snowfall in winter, which feeds perennial rivers like the Ganga and Brahmaputra. Without the Himalayas, India would have been a cold desert with little rainfall, completely altering its climate, vegetation, and agriculture.
Q12. Why does Rajasthan receive scanty rainfall? Explain.
Ans: Rajasthan receives scanty rainfall due to geographical and relief-related reasons. The Aravalli Hills, instead of obstructing the southwest monsoon, run parallel to its path, providing no barrier. Hence, the winds pass without shedding much moisture. Moreover, Rajasthan lies in the rain-shadow region where monsoon winds lose most of their moisture before reaching. Additionally, the region experiences hot, dry winds like loo, which increase evaporation and aridity. Annual rainfall is often less than 25 cm, making Rajasthan semi-arid to arid. These conditions make agriculture dependent on irrigation and drought-resistant crops.
Q13. What are Mango showers? How do they affect agriculture?
Ans: Mango showers are pre-monsoon rains that occur in Karnataka and Kerala during April and May. These localised rains are caused by convectional currents. They are called mango showers because they help in the early ripening of mangoes. They are also beneficial for coffee plantations in Karnataka. Although light, they mark the transition from the hot weather season to the southwest monsoon. For farmers, mango showers are important as they prepare the soil for the upcoming rainy season. Thus, these showers influence agricultural activities and local economy in peninsular India.
Q14. Explain the main features of the hot weather season in India.
Ans: The hot weather season lasts from March to May. Temperatures rise steadily, with northwestern India experiencing extremely hot conditions. The loo, hot and dry winds, blow across Punjab, Haryana, and Uttar Pradesh. Localised storms occur, such as Kalbaisakhi in Bengal and Assam, bringing thunderstorms and rainfall. In Kerala and Karnataka, mango showers help crops. This season is marked by intense heat waves in central and north India, while coastal regions remain comparatively cooler due to the moderating effect of the sea. Hence, the hot weather season is both harsh and agriculturally significant.
Q15. Why do coastal areas have equable climate? Explain with examples.
Ans: Coastal areas experience equable climate because of the moderating influence of the sea. Water heats and cools more slowly than land, so areas near the sea do not experience extreme temperatures. For example, Mumbai has mild summers and winters compared to interior cities like Nagpur or Delhi. This results in smaller temperature range between summer and winter. The sea breeze and land breeze also help regulate temperature daily. Thus, coastal regions enjoy moderate conditions suitable for human settlements and agriculture, unlike continental interiors which face extremes.
Q16. Explain how monsoon acts as a unifying bond in India.
Ans: The monsoon is often described as a unifying bond for India. Its arrival is eagerly awaited across the country, as agriculture, which supports two-thirds of the population, depends on monsoon rains. Cultural festivals like Onam, Bihu, and Pongal are linked to monsoon. Despite regional variations, the monsoon binds the nation in shared anticipation and relief. It also influences industries like hydroelectric power and water supply. Even films, literature, and songs reflect monsoon’s significance. Thus, though uncertain, monsoon rains unite India socially, economically, and culturally, making it a central feature of national life.
Q17. Why is the Indian monsoon considered uncertain?
Ans: The Indian monsoon is considered uncertain because both its arrival and distribution vary greatly each year. Sometimes it arrives early, sometimes late. Rainfall may be heavy in one region but scanty in another. The total amount of rainfall also fluctuates due to global phenomena like El Niño and La Niña, which disturb ocean-atmosphere balance. For example, drought years affect crops like rice and sugarcane, while flood years damage infrastructure. This uncertainty makes agriculture risky, as farmers cannot always depend on timely rains. Thus, the unpredictability of the monsoon remains a challenge for India’s economy and society.
Q18. Describe the retreating monsoon season.
Ans: The retreating monsoon occurs from October to November. During this season, the southwest monsoon withdraws from northern plains. Skies become clear, and temperatures rise due to strong sunlight, causing October heat. The winds blow from land to sea, and most of the country becomes dry. However, the Tamil Nadu coast receives significant rainfall from the northeast monsoon winds that pick up moisture from the Bay of Bengal. Cyclonic depressions from the Bay also cause heavy rains in Odisha and Andhra Pradesh. The retreating monsoon is thus marked by contrasting features of dryness and rainfall.
Q19. Explain three major features of India’s monsoon rainfall.
Ans: India’s monsoon rainfall has three major features: Seasonality, as rainfall is concentrated between June and September; Uneven distribution, since some areas like Mawsynram receive more than 11000 mm annually, while Rajasthan receives less than 25 cm; and Uncertainty, as both timing and amount vary each year due to global climatic factors. This variability affects agriculture, economy, and water resources, making monsoon both a boon and a challenge. These features highlight why the monsoon is central to India’s climatic and social fabric.
Q20. What is the importance of monsoon rainfall for India’s agriculture and economy?
Ans: Monsoon rainfall is vital as nearly 64% of India’s cultivated land depends on it. Crops like rice, jute, and sugarcane are entirely rain-fed. Adequate monsoon ensures good harvest, leading to food security, rural employment, and economic stability. A weak monsoon, however, leads to drought, crop failure, inflation, and hardship for farmers. Monsoon rains also replenish groundwater, fill reservoirs, and support hydroelectric projects. Socially, festivals and cultural activities are linked to the monsoon. Thus, the Indian economy is often described as a “gamble on the monsoon,” reflecting its immense importance.
Part E – Case Based QAs
Case Study 1 – The Arrival of Monsoon in Kerala
In early June, dark clouds gather over the Arabian Sea, and the southwest monsoon strikes the Kerala coast. Within a few days, the entire state experiences heavy downpours, marking the beginning of the rainy season in India. Farmers eagerly wait for this event, as it signals the sowing season for rice and other crops. The sudden shift from scorching summer to torrential rains is referred to as the “burst” of the monsoon.
Q1. Why is the arrival of monsoon in Kerala significant for India?
Ans: It marks the onset of monsoon in the country, which gradually advances northward to cover the whole nation.
Q2. Explain the meaning of “burst of monsoon.”
Ans: It refers to the sudden, heavy rainfall that occurs after a prolonged hot and dry summer season.
Q3. How does monsoon arrival influence agriculture?
Ans: It initiates the sowing of Kharif crops like rice, maize, and pulses, on which millions of farmers depend.
Case Study 2 – Western Disturbances in Winter
During January, parts of Punjab, Haryana, and Delhi receive unexpected rainfall. This winter rainfall comes from cyclonic systems called western disturbances, originating in the Mediterranean region and brought to India by westerly jet streams. Though limited in quantity, this rainfall is extremely beneficial for rabi crops like wheat and mustard. However, excessive rain or hail may also damage crops.
Q1. What are western disturbances?
Ans: They are cyclonic systems from the Mediterranean Sea, bringing winter rain to northwestern India.
Q2. Why are they important for Indian agriculture?
Ans: They provide crucial winter rain for rabi crops such as wheat, barley, and mustard.
Q3. How can western disturbances harm agriculture?
Ans: If excessive, they may lead to hailstorms, lodging of crops, and reduced yields.
Case Study 3 – The Retreating Monsoon
By October, the monsoon winds begin to withdraw from northern India. Clear skies, high daytime temperatures, and high humidity create uncomfortable weather known as October heat. During this period, the Tamil Nadu coast receives rainfall due to moisture picked up by the northeast monsoon winds from the Bay of Bengal. This rainfall is vital for agriculture in Tamil Nadu, where other regions of India experience dryness.
Q1. What is October heat?
Ans: It is the hot and humid weather experienced after the withdrawal of the southwest monsoon.
Q2. Why does Tamil Nadu receive rainfall during retreating monsoon?
Ans: The northeast winds blow over the Bay of Bengal, collect moisture, and strike Tamil Nadu’s coast.
Q3. How is this rainfall important for Tamil Nadu?
Ans: It supports rice cultivation and other agricultural activities in the state.
Case Study 4 – Mawsynram: The Wettest Place
Mawsynram in Meghalaya receives the highest average rainfall in the world. The Bay of Bengal branch of monsoon strikes the Khasi Hills and is forced to rise, causing extremely heavy rainfall. This region experiences frequent landslides and floods but also benefits from lush forests and unique biodiversity. The heavy rainfall also affects the lifestyle of local people, who often use grass to waterproof their homes.
Q1. Why does Mawsynram receive such heavy rainfall?
Ans: Moisture-laden monsoon winds are trapped by the Khasi Hills, causing intense rainfall.
Q2. Mention one advantage and one disadvantage of this heavy rainfall.
Ans: Advantage – supports dense forests and agriculture. Disadvantage – causes floods and landslides.
Q3. How do people adapt to such climatic conditions?
Ans: They use traditional methods like grass roofing to protect against heavy rains.
Case Study 5 – The Role of Himalayas in Climate
The Himalayas act as a climate barrier for India. In winter, they prevent icy winds from Central Asia, keeping northern India warmer. In summer, they obstruct the southwest monsoon winds, forcing them to shed moisture in India instead of passing into Central Asia. Without the Himalayas, India would have been a desert-like landmass with extreme climate.
Q1. How do the Himalayas protect India in winter?
Ans: They block cold winds from Central Asia, preventing severe winter conditions.
Q2. How do they influence the monsoon in summer?
Ans: They obstruct moisture-laden monsoon winds, causing rainfall across northern India.
Q3. What would India’s climate be like without the Himalayas?
Ans: It would be extremely dry, with little rainfall, resembling a desert.
Case Study 6 – Drought in Rajasthan
Western Rajasthan frequently experiences drought due to very low rainfall. The Aravalli Hills run parallel to the direction of the monsoon winds, failing to block them. As a result, moisture-laden winds pass without shedding rain. Rajasthan lies in a rain-shadow zone, and the desert climate makes agriculture highly dependent on irrigation projects like the Indira Gandhi Canal.
Q1. Why does Rajasthan receive scanty rainfall?
Ans: Because Aravallis do not obstruct monsoon winds and the region lies in a rain-shadow zone.
Q2. How does drought affect agriculture in Rajasthan?
Ans: It reduces crop yield, making farming highly dependent on irrigation.
Q3. Name one irrigation project that supports Rajasthan agriculture.
Ans: The Indira Gandhi Canal.
Case Study 7 – El Niño and Indian Monsoon
In some years, the Indian monsoon weakens, leading to drought-like conditions. One major reason is El Niño, a phenomenon where the surface waters of the Pacific Ocean near South America become unusually warm. This affects global wind patterns and weakens the Indian monsoon. Farmers suffer losses, and food production declines, creating challenges for the economy.
Q1. What is El Niño?
Ans: It is the abnormal warming of Pacific Ocean waters, disturbing global wind and rainfall patterns.
Q2. How does El Niño affect the Indian monsoon?
Ans: It weakens the monsoon, causing poor rainfall and droughts.
Q3. How does a weak monsoon affect the economy?
Ans: It reduces agricultural output, leading to food scarcity and inflation.
Case Study 8 – Kal Baisakhi in Bengal
During the hot weather season (March–May), sudden violent thunderstorms called Kal Baisakhi occur in West Bengal and Assam. These storms bring heavy rain, thunder, and lightning, providing temporary relief from heat but also causing damage to crops and houses. Farmers, however, benefit from the rain that supports jute and rice cultivation.
Q1. What is Kal Baisakhi?
Ans: It is a local thunderstorm occurring in Bengal and Assam during summer.
Q2. What are its positive and negative effects?
Ans: Positive – provides relief from heat and supports crops. Negative – damages houses and standing crops.
Q3. Name two crops benefitted by Kal Baisakhi.
Ans: Jute and rice.
Case Study 9 – Equable Climate of Mumbai
Mumbai, located on the western coast, experiences moderate temperatures throughout the year. Summers are not very hot, and winters are not very cold due to the moderating influence of the Arabian Sea. Unlike Delhi, where temperatures vary greatly, Mumbai’s equable climate supports year-round economic activities and attracts people from across the country.
Q1. Why does Mumbai have an equable climate?
Ans: Because of the moderating influence of the sea, which controls temperature variations.
Q2. How is Mumbai’s climate different from Delhi’s?
Ans: Mumbai has mild summers and winters, while Delhi experiences extreme heat and cold.
Q3. How does equable climate benefit Mumbai?
Ans: It allows continuous business and industrial activities without weather disruptions.
Case Study 10 – Importance of Monsoon for Indian Economy
Nearly 65% of India’s population depends on agriculture, which is largely rain-fed. A good monsoon ensures bumper crops, reduces food imports, and boosts the economy. On the other hand, a weak monsoon leads to droughts, food scarcity, and inflation. Monsoon rains also replenish groundwater, support hydropower generation, and influence cultural festivals. Thus, the monsoon acts as a unifying bond for India.
Q1. Why is monsoon vital for Indian agriculture?
Ans: Because most of India’s farmland is rain-fed, and crops depend on timely monsoon rains.
Q2. Mention two economic benefits of a good monsoon.
Ans: Ensures food security and boosts rural income, supporting overall economic growth.
Q3. How does monsoon influence Indian culture?
Ans: Many festivals, traditions, and agricultural practices revolve around the arrival or retreat of the monsoon.