Kerala Syllabus Class 10 Social Science II: Chapter 01 Weather and Climate - Questions and Answers


Questions and Answers for Class 10th Social Science II (English Medium) ദിനാന്തരീക്ഷസ്ഥിതിയും കാലാവസ്ഥയും | SSLC Text Books Solution Geography (English Medium) Geography: Chapter 01 Weather and Climate - Unit summary - Questions and Answers

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Class 10 Social Science II - Weather and Climate - Questions and Answers
∎SSLC Social Science II (English Medium Notes)

1. What are the Elements of Weather?
The atmospheric conditions of any place depend on the factors such as temperature, pressure, wind and humidity. They in turn, are influenced by the amount of sunlight available there. Hence these are called Elements of Weather

2. What is weather?
Atmospheric conditions such as temperature, pressure, wind, humidity and precipitation for a shorter period of time are termed as Weather.

3. How is climate different from weather?
The average weather condition experienced for a longer period over a larger area is termed as the Climate.
The climate of a place is determined by considering the weather conditions of about 35 to 40 years. 

4. How do climatic conditions influence various aspects of life?
• Diverse Flora and Fauna
• Food habits
• Dressing
• Settlement
• Occupation
• Physical and mental conditions
• Colour and race of mankind 
• Agriculture
• Transportation and Communication

5. What process produces energy in the sun?
Nuclear fusion.

6. What is insolation?
The amount of sun's rays reaching the earth's surface is called insolation

7. What are the major processes through which heat is transferred from the Earth's surface to the atmosphere? 
Conduction, Convection, Advection, and Radiation.
• Conduction: Heat is transferred to the lower part of the atmosphere which is directly in contact with the surface of the earth.
• Convection: As the heated air expands and rises up, heat is transferred to higher
reaches of the atmosphere.
• Advection: Heat is transferred horizontally through wind.
• Radiation: Emission of energy in the form of long waves after the earth’s surface gets heated up.

8. What is the difference between insolation and terrestrial radiation?
• Solar energy reaches the earth in the form of short waves. This is called Insolation.
• Heat is transferred from the surface of the earth to outer space in the form of long waves. This is called terrestrial radiation.

9. What is the Greenhouse Effect? 
The absorption of terrestrial radiation by the atmospheric gases such as carbon dioxide heats up the atmosphere. This phenomenon is termed as Green House Effect. 

10. What is the Heat Budget of the Earth? 
Almost entire energy reaching the earth as insolation is radiated back every day Thus the surface temperature of the earth remains balanced without becoming extremely hot or cold. This process of heat balancing is called the Heat Budget of the Earth. 

11. Discuss the importance of heat budget in sustaining the earth as a life supporting planet.
• Keeps Temperatures Just Right - It stops Earth from getting too hot or too cold, making it comfortable for living things.
• Helps Keep the Climate Stable - A steady climate allows plants, animals, and humans to live and grow over time.
• Supports the Water Cycle - The Sun's heat helps water evaporate and fall again as rain, which all life needs.
• Moves Air Around the Earth - Heat causes winds and weather that spread warmth and rain to different places.
• Moves Ocean Water - Ocean currents carry warm and cold water around the planet, helping to control temperatures.
• Prevents Extreme Changes - A balanced heat budget stops Earth from freezing or overheating. 

12. According to meteorologists, at what time of day is the maximum temperature typically recorded and why?
The surface temperature of the earth gradually increases by the flow of insolation since the sun rise and attains the maximum by the noon. As the atmosphere is heated through various processes of heat transfer, it takes more time for the atmosphere to get heated up than the time taken for the earth's surface. Thus, the temperature recorded at 2 pm is considered as the maximum temperature of the day by the meteorologists

13. What time of day is generally associated with the minimum temperature, and what causes this? 
The surface temperature of the earth gradually decreases in the afternoon due to the decrease in intensity of insolation as well as the simultaneous terrestrial radiation. The earth's surface as well as the atmosphere get cooled by more energy loss through terrestrial radiation during night. Thus, the temperature recorded just before the sun rise is considered as the minimum temperature of the day.

14. What instrument is used to measure Atmospheric temperature?
• Atmospheric temperature is measured using an instrument called Thermometer.
• A Maximum-Minimum thermometer is a special type of thermometer used to measure the highest and lowest temperatures of a day.

15. What is the diurnal range of temperature?
Diurnal range of temperature is the difference between the maximum temperature and the minimum temperature of a day.
Diurnal Range = Maximum temperature – Minimum temperature

16. What is the daily mean temperature?
The average temperature of a day is called as Daily mean temperature 
            Daily mean temperature =
Maximum temperature + Minimum temperature of the day
                                           2

17. Calculate the diurnal range of temperature and the daily mean temperature if the maximum and minimum temperatures of a place are 36º C and 28º C respectively.
Maximum Temperature = 36°C
Minimum Temperature = 28°C
• Diurnal Range of Temperature = Maximum Temperature – Minimum Temperature
= 36°C – 28°C = 8°C
• Daily Mean Temperature = (Maximum Temperature + Minimum Temperature) ÷ 2
= (36°C + 28°C) ÷ 2
= 64°C ÷ 2 = 32°C
18. What are isotherms?
Plotting the temperature recorded at specific places, smooth curved lines are drawn connecting the places having equal temperature. These imaginary lines are called Isotherms. 

19. Why are the isotherms generally curved in the northern hemisphere?
• Comparatively land area is more than the ocean in the Northern Hemisphere.
• The isotherms are generally curved because of the differential heating of land and sea.

20. Compared to the Northern Hemisphere, Isotherms are more or less parallel to the latitudes in the Southern Hemisphere. Why?
In the southern hemisphere, we have more water mass as compared to landmass and hence isotherms are regular in nature. The bending of isotherms is due to the differential heating of land and water. That is why Isotherms in the southern hemisphere are almost parallel to the Equator compared to those in the northern hemisphere.

21. What are the factors influencing the distribution of temperature?
• Latitude
Very high temperature is experienced along the equatorial regions where the incidence of sun’s rays is almost vertical.
Owing to the spherical shape of the earth, the incidence of sun’s rays are more inclined away from the equator towards the poles. Thus the temperature gradually decreases towards both the poles.
• Altitude
Atmospheric temperature gradually decreases with increase in altitude. 
• Differential Heating of Land and Sea
Compared to sea, land gets heated and cooled at a faster rate. Thus the land areas experience higher summer temperature and lower winter temperature, when compared to sea.
• Distance from the Sea
The winds blowing from land to sea and vice versa help to moderate the temperature experienced along coastal areas. Away from the sea, the maritime influence gradually decreases to cause very high day temperature and low night temperature.
• Ocean Currents
The temperature along the coastal regions is raised or lowered by the warm currents and cold currents  respectively as they pass by. For example, the warm current called North Atlantic Current gives relief for the Western European countries from severe cold. On the other hand, the places situated along the North Eastern Canada, which are also in the same latitude, experience severe cold for months due to the influence of Labrador cold current.
• Relief
The availability of sunlight differs from one place to another in accordance with the relief. Due to this difference, the mountain slopes facing the sun experience higher temperature and opposite slopes experience lower temperature.

22. What is the Normal lapse rate?
The phenomenon of gradual decrease in temperature at the rate of 6.4º Celsius per kilometre of altitude is termed as Normal Lapse Rate.

23. Observe the diagram (Textbook Page: 14, Fig. 1.5). Familiarise the temperature zones and identify the latitudes between which these zones are located.
• Torrid Zone (Tropical) -  It's located between the Tropic of Cancer (23.5° N) and the Tropic of Capricorn (23.5° S). 
• Temperate Zone - It's located between the Arctic Circle (66.5° N) and Tropic of Cancer  (23.5° N) and the region between the Tropic of Capricorn (23.5° S) and the Antarctic Circle (66.5° S).
• Frigid Zone - It's located between the Arctic Circle (66.5° N) and the North Pole (90° N) in the Northern Hemisphere, and between the Antarctic Circle (66.5° S) and the South Pole (90° S) in the Southern Hemisphere. 

24. Why do we generally experience low temperature at places situated at higher elevations such as Ooty, Munnar and Kodaikanal?
Atmospheric temperature gradually decreases with an increase in altitude. This is why we generally experience low temperatures at places situated at higher elevations, such as Ooty, Munnar and Kodaikanal.

25. Diurnal range of temperature is generally low in Kerala. Why?
Temperature remains moderate at places close to the sea. Because of the influence of the Arabian Sea to the west, Kerala experiences a moderate temperature.

26. Why temperature remains moderate at places close to the sea?
This is because the heating of land causes the wind to blow from sea to land and the cooling of land causes the wind to blow from land to sea. so Moderate temperatures prevail in areas close to the sea.

27. What is Atmospheric Pressure?
The weight exerted by the atmospheric air over the Earth’s surface is termed as Atmospheric Pressure.
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28. What are the factors affecting atmospheric pressure?
• Temperature
• Altitude
• Humidity

i. Temperature and atmospheric pressure: Atmospheric air expands on getting heated and rises up. Thus low pressure regions are formed. This rising air gradually cools, contracts and subsides to form high pressure regions. The atmospheric pressure and temperature are inversely proportional.

ii. Atmospheric pressure and altitude: As the density of atmospheric gases decreases with increase in altitude, atmospheric pressure gradually decreases. The vertical variation of atmospheric pressure is at the rate of about 1mb per 10 metres. The atmospheric pressure and altitude are inversely proportional.

iii. Humidity and atmospheric pressure: As the humidity increases, the water molecules displace the heavier gases in the atmosphere like nitrogen and oxygen. The atmospheric pressure becomes low, as humid air is lighter than dry air. Humidity and atmospheric pressure are inversely proportional.

29. Why do we feel discomfort like clogging of ears while travelling to higher elevations?
When you travel to higher places, atmospheric pressure gradually decreases, but your ears take time to adjust. This causes a clogged feeling because the pressure inside your ears is different from the outside air.

30. Coastal regions experience comparatively lower atmospheric pressure than interior locations. Why?
Coastal regions experience lower atmospheric pressure than interior areas mainly due to the higher humidity from nearby oceans, as moist air is less dense than dry air. 

31. What are Isobars?
Smooth curved lines are drawn on maps to connect places having equal atmospheric pressure. These imaginary lines are called Isobars.

32. Write the correct statement
a. Pressure decreases with altitude.
b. As the altitude increases, the pressure decreases.
Answer:
b. As the altitude increases, the pressure decreases.
33. Describe the global pressure belts
Distinct pressure conditions prevail at certain specific zones due to the influence of the rotation of the earth. Different pressure belts are formed along certain specific latitudinal zones. These are called Global Pressure Belts.
i. Equatorial low-pressure belt (0° to 5°N & S): The expansion and rising up of air due to high temperature prevailing in the equatorial region is the cause for the formation of Equatorial Low Pressure Belt. This zone of vertical air currents is devoid of winds. Being the windless zone, this pressure belt is called Doldrum.

ii. Subtropical high-pressure belt (30°N & 30 °S): The rising warm air along the equatorial region moves polewards as upper air winds which gradually cool and subside at about 30º North and 30º South latitudes. This results in the formation of Subtropical High Pressure Belts.

iii. Subpolar low-pressure belt (60°N & 60°S latitudes): At about 60º North and 60º South latitudes, normally high-pressure zones should be formed due to lower temperature conditions. But owing to the continuous throwing up of air along these regions caused by the influence of the rotation of the earth, Sub Polar Low Pressure Belts are formed.

iv. Polar high-pressure belt (90°N & 90°S): This zone experiences severe cold throughout the year. Polar High Pressure Belts are formed as a result of the contraction and subsidence of cold air.

34. Describe the shift of the pressure belts.
As the temperature conditions vary with the apparent movement of the sun, the global pressure belts are subjected to relative shifts.  Global pressure belts may shift to about 5º to 10º northwards during summer season and shift southward during winter season. This shifting of global pressure belts has decisive influence on global climate.

35. What are the two types of air movements in the atmosphere?
There are two types of air movements in the atmosphere – Air Currents and Winds. Air Currents are the vertical movements of air and Winds are the horizontal movements of air from high-pressure areas to low-pressure areas.

36. How are winds named?
Winds are named according to the direction from which they blow. For example, the winds blowing from the southwest are termed as southwest winds and the winds blowing from the sea towards the land are termed as sea breezes.

37. What is the name given to the monsoon winds blowing towards the northeast direction in India?
Northeast monsoon winds

38. What is the name given to the monsoon winds blowing towards the southeast direction in India?
South West Monsoon winds

39. What are the factors that control the speed and direction of the winds?
• Coriolis force
• Pressure gradient force
• Frictional force

40. What is the Coriolis Force?
Freely moving bodies get deflected to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. This is due to the force generated as a result of Earth's rotation, which is known as the Coriolis force.

41. How does the Coriolis Force affect the direction of winds?
Owing to the Coriolis effect, the winds will deflect towards the right of its direction in the Northern Hemisphere and towards the left of its direction in the Southern Hemisphere.

42. What is the Pressure gradient force, and how does it affect wind speed?
Pressure gradient is the change in pressure over a horizontal distance. If there is considerable change in pressure between nearby places, it indicates high pressure gradient. If there is no considerable difference of pressure over horizontal distance, pressure gradient is said to be low. At places where there is high pressure gradient, winds will be strong.

43. Analyse the patterns of isobars given below and find out where the winds are strong. (Put a tick mark)
44. What is the frictional force, and how does it affect wind speed?
The friction caused by hills, mountains, forests and man-made structures will obstruct the free flow of winds.

45. Winds are comparatively stronger over oceans than over continents. Why?
The speed of wind will be high over ocean surfaces and plains as the friction is less. On the other hand, the friction being more along difficult terrains and places with dense forest cover, the speed of wind will be less in those places.
46. What are the different types of winds?
• Permanent Winds
• Periodic Winds
• Local Winds
• Variable Winds

47. What are Permanent Winds?   
• The winds blowing constantly over a particular direction throughout the year are called Permanent winds.  
• These winds are also known as prevailing winds and planetary winds. 
• These winds blow between global pressure belts. 
• Trade winds, Westerlies and Polar winds are the major permanent winds.

48. Observe the diagram (Textbook Page 22, Fig 1.17) and identify the pressure belts between which each of these permanent winds blows.
Permanent Winds Pressure belts 
• Trade winds• From the subtropical high-pressure belts to the equatorial low-pressure belt (30°N & 30°S latitude to 0°)
• Westerlies• From the subtropical high-pressure belts (30° latitudes) into the Subpolar low-pressure belts (60° latitudes) in both hemispheres.
• Polar Winds• From the polar high-pressure belts (90° latitudes)  to the subpolar low-pressure belts (60° latitudes) in both hemispheres.
49. Trade winds are North Easterlies in the Northern Hemisphere and are South Easterlies in the Southern Hemisphere. Why?
Due to the Coriolis effect, trade winds in the Northern Hemisphere deflect to the right of their original direction. As these winds blow from the northeast, they are known as the northeast trade winds.
Similarly, in the Southern Hemisphere, trade winds deflect to the left of their original direction. Since these winds blow from the southeast, they are called the southeast trade winds.

50. Westerlies are comparatively stronger in the Southern Hemisphere than in the Northern Hemisphere. Why?
• The speed of wind will be high over ocean surfaces and plains as the friction is less.
• Due to the vast expanse of oceans in the Southern Hemisphere, the westerlies are stronger in the Southern Hemisphere than in the Northern Hemisphere.

51. What are Periodic Winds?
• Winds subjected to the periodic reversal of their direction are termed as Periodic winds. 
• Land breezes, sea breezes, mountain breezes, valley breezes and the monsoon winds are periodic Winds

52. Illustrate the land breezes and sea breezes and write a note on their formation in your notebook.
i. Sea breeze
• The air in contact with the land gets heated up and ascends as the land heats up quickly during the daytime.
• This leads to the formation of low pressure over the land.
• which causes the comparatively cooler air to blow from the sea to land.
• This is known as the sea breeze.

ii. Land breeze.
• As the land cools faster than the sea during the night it would be high pressure over the land and low pressure over the sea.
• This results in the movement of air from the land to the sea.
• This is the land breeze.
• The land breeze which starts blowing at night becomes active early in the morning and ceases by sunrise.

53. Mountain Breezes and Valley Breezes.
• During night, air along the mountain slopes cools, contracts and moves down slope. These winds are called mountain breezes.
• During day time, the heating by sunlight and rising up of air along the mountain slopes make the wind to blow up slope from the valley. These winds are called valley breezes.

54. Prepare a description of the South West Monsoon winds.
The term ‘monsoon’ implies the seasonal reversal in the wind pattern. During summer the South Asian land masses, especially the Indian Sub Continent, gets heated up intensely and severe low pressure develops. Wind blows towards the land mass from the Indian Ocean where comparatively high pressure prevails. These winds blowing as South West winds due to Coriolis effect causes widespread rainfall on entering the land. This is Southwest monsoon.

55. Prepare a description of the Northeast Monsoon winds.
During winter, as the northern land masses get severely cooled, high pressure develops over North India. This causes the winds to blow continuously from the land towards the Indian Ocean as north east winds. These winds which are generally dry in nature are called Northeast monsoon winds.

56. How are the Local Winds formed?
Local winds are winds formed as a result of local differences in temperature and pressure in different parts of the world. Most of the local winds are periodic in nature. These winds are known by local regional names. 

57. Prepare a table showing important local winds and their characteristic features.
Local winds Region Characteristics
LooNorth Indian Plains

Hot wind

ChinookSlopes of Rocky Mountains in North America

Dry hot wind

FoehnSlopes of Alps Mountain in Europe

Dry hot wind

HarmattanSahara Desert in Africa

Relief to intense heat

58. What is variable Winds?
Winds of short duration, of which the intensity or direction cannot be predicted, are called variable winds. Cyclones and Anticyclones are variable winds.
59. Cyclones
• Cyclones are low-pressure systems towards which winds whirl from the surroundings.
• The direction of flow of air into the cyclones are anticlockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere.

60. Compare the tropical cyclones with temperate cyclones and prepare a note.
i. Tropical cyclones 
• Tropical cyclones originate over tropical oceans. 
• The tropical cyclones moving in northwest direction over the oceans, get dissipated on hitting the lands. 
• Different temperature conditions prevailing on land and also the friction causes the dissipation of cyclones on entering land. 
• The tropical cyclones cause intense rainfall and strong whirlwinds along the coasts. 
• They are known by different names in different parts of the world such as Hurricanes, Typhoons, Willy Willies, Tornadoes etc.

ii. Temperate cyclones
• Temperate cyclones are formed in temperate regions where warm and cold air masses meet.
• Even if the temperate cyclones are larger in diameter, they are less devastating. • Unlike tropical cyclones, these low-pressure systems can move over land also.

61. Anticyclones
• Anticyclones are high pressure system from which winds whirl outwards. Generally
anticyclones do not cause atmospheric disturbances. 
• The direction of flow of winds from anticyclones is clockwise in the Northern Hemisphere and anticlockwise in the Southern Hemisphere.

62. What is atmospheric humidity?
The invisible water content in the atmosphere is called Humidity.

63. Name the process by which water turns to water vapour.
Evaporation

64. What are the sources through which water vapour reaches the atmosphere?
• Evaporation – The sun's heat causes water from oceans, lakes, rivers, and other bodies of water to turn into vapour and rise into the air.
• Transpiration – Plants release water vapour through tiny pores in their leaves during photosynthesis.
• Sublimation – Ice and snow can turn directly into water vapour without melting first, especially in cold but dry conditions.
• Volcanic Activity – Volcanoes emit water vapour along with gases during eruptions.

65. Explain the following concepts in relation to atmospheric humidity.
i.  Absolute humidity
ii. Relative humidity
iii. Saturation level and Saturation point

i.  Absolute humidity: Actual amount of water vapour present per unit volume of
atmosphere is called Absolute humidity.

ii. Relative humidity: The ratio between the actual amount of water present in the atmosphere and the total waterholding capacity of atmosphere at that particular temperature and time is referred to as Relative Humidity. It is expressed in percentage.
iii. Saturation level: The state at which the atmosphere is fully saturated with moisture/water vapour is known as saturation level. The temperature at which this level is attained is termed as saturation point.

66. At the saturation level, what may be the relative humidity in percentage?
At the saturation level, the relative humidity is 100%.

67. Which instrument is used to measure atmospheric humidity? 
Hygrometer is the instrument used to measure atmospheric humidity. 

68. How can Relative humidity be estimated using wet and dry bulb thermometers?
Relative humidity can be estimated based on the difference in temperature recorded in wet and dry bulb thermometers.

69. What is condensation?
When the atmosphere is fully saturated with water vapour, condensation begins. The process by which water vapour cools down to a liquid state is called condensation.

70. What are the different forms of condensation?
• Dew: During the night, as the earth’s surface cools down, the atmosphere close to the earth’s surface also  cools. The water vapour condenses to form tiny droplets of water which may cling on to the grass tips, leaf blades as well as other cold surfaces.

• Frost: Whenever the atmospheric temperature falls below 0º Celsius, especially during nights, tiny crystals of ice are formed instead of dew.

• Mist and Fog: When the atmosphere gets cooled, the water vapour condenses to form tiny droplets of water and remains suspended  in the lower atmosphere. Fog or mist is formed as a result of condensation of water vapour around tiny dust particles in the lower atmosphere. Fog and mist can be distinguished based on the range of visibility through them.  

• Clouds: Clouds are formed as a result of condensation around the tiny dust particles in the atmosphere. The water droplets thus formed are less than 0.001 cm in diameter. This is why, they remain suspended in the atmosphere.
71. Clouds can be classified according to their form and height. Explain
Clouds can be classified based on their form as well as the height at which
they are formed.
• Cirrus clouds: Thin, delicate, feather-like clouds formed at very high altitudes are called Cirrus clouds.

• Stratus clouds: Thick-layered clouds, usually formed in the lower atmosphere, are called Stratus clouds.

• Cumulus clouds: Cotton wool-like clouds formed as a result of intense convection currents, are called Cumulus clouds. These clouds have great vertical development.

• Nimbus clouds: Dark, rain-bearing clouds, formed in the lower part of the atmosphere, are called Nimbus clouds. The dark colour is due to the thick concentration of water droplets which does not allow light to penetrate through them.

• The clouds mentioned above are not usually seen independently. Mostly we see the combinations of different types of clouds. Such clouds are called as cirro stratus, strato cumulus, cumulo nimbus, nimbo stratus etc.

72. What is precipitation? 
As a result of continuous condensation, the size of water droplets within the clouds gradually increases. As the size of water droplets grows beyond the limit of  resistance against gravity, water droplets will be released from the clouds and may fall on earth in various forms. This is termed as precipitation. Rainfall, snow fall and hailstones are the different forms of precipitation.

73. What are the different forms of precipitation?
Rainfall, snow fall and hailstones are the different forms of precipitation.

• Rainfall: Rainfall is the common and familiar manifestation of precipitation which is in the form of water droplets.

• Snowfall: Temperature falls below 0º Celsius in cold climatic regions as well as in temperate regions during winter. In such places, precipitation occurs in the form of tiny crystals of ice. This form of precipitation is called snowfall.

• Hailstones: The water droplets released from the clouds are subjected to repeated condensation at different levels of atmosphere. It reaches the earth in the form layered ice pellets. These are termed as hailstones.

74. Is hailstone a winter phenomena? Inquire.
Hail is not a winter phenomenon; it typically occurs during warm months, especially spring and summer. It forms in strong thunderstorms with intense updrafts, not in snowstorms. Unlike snow or sleet, hail develops high in cumulonimbus clouds where supercooled water freezes into ice.

75. What is the form of precipitation most familiar to you?
Rainfall

76. Explain the different types of rainfall.
i. Orographic rainfall: Moisture-laden winds from the sea enter the land and will be raised along the mountain slopes. This leads to condensation and formation of rain clouds along the windward slopes of mountains. Rainfall occurring in this manner is called Orographic rainfall or Relief rainfall or Relief rainfall.

ii. Convectional rainfall: The surface air that is heated up rises in the atmosphere along with water vapour. At higher altitudes, they become cooler and condense to fall as rain. As the convectional rainfall commonly occurs during afternoons, it is also called 4 O’Clock rains.

iv. Cyclonic Rainfall: In cyclonic systems where warm and cold air meet, the warm air will be raised up to cause condensation and rainfall. This type of rainfall is called Cyclonic Rainfall.  As the boundary lines between warm and cold air masses are known as fronts, this type of rainfall are also called Frontal Rainfall.

77. What do you meant by Rainshadow regions?
While the windward slopes of mountains get plenty of rainfall, the descending dry air makes the leeward side rainless. Such regions are called Rain Shadow Regions.

78. While Kerala receives Southwest monsoon rains, the western parts of Tamil Nadu receives very little rainfall. Why?
The Western Ghats block Southwest Monsoon winds. Kerala, on the windward side, receives heavy rainfall. In contrast, western Tamil Nadu, on the leeward side in the rain shadow region, loses most of its moisture, leading to low rainfall.

79. Which form of rainfall is common in the equatorial climate zone?
Convectional rainfall

80. In equatorial climatic regions conventional rainfall is a diurnal phenomenon. Why?
In equatorial climatic regions, convectional rainfall is a diurnal phenomenon because of intense solar heating during the day. As the sun heats the surface, warm air rises, carrying moisture with it. This leads to the formation of cumulonimbus clouds, resulting in heavy rainfall, usually in the afternoon or evening. Since temperatures remain high throughout the year, this process repeats daily, making convectional rainfall a regular occurrence in equatorial zones

81. Why the South-West monsoon rainfall is not received in Tamil Nadu?
Tamil Nadu is situated in the rain shadow region of Western Ghats.



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