Ramana Vidyalaya (CBSE), Sholinganallur

Worksheet No - 10 - Answer Key

CLIMATE (September 2024)
Name : Date:
Grade : IX Subject: S.SC/Geography
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SECTION-A
I. SECTION-A - Objective Questions
I Answer the following questions in one word/ in a sentence or two:
1. Climate refers to the sum total of weather conditions and variations over a large area for a long
period of time.
2. Weather refers to the state of atmosphere over an area at any point of time.
3. The generalised monthly atmospheric conditions is called season
4. The climate of India is described as the Monsoon type.
5. Match the following:

a. Away from the Latitude i. Lower atmospheric density

b. Higher altitude ii. Lower temperature

c. Lower pressure iii. Moderate temperature

d. Closer to the sea iv. Higher temperature

e. Hot air v. Dry climate

f. Cold current vi. Raises up

Ans: a-ii, b-i, c-iv, d-iii, e-vi, f-v
6. What do you mean by coriolis effect
Ans: The deflection of the northern winds towards right and southern winds towards left due to
the rotation of the earth is called coriolis effect.
7. Name the two monsoon winds that spread to India and give rain.
Ans: i. North Easterly winds
ii. South Western Monsoon winds
8. Give reason why coastal areas do not experience much variation in the temperature.
Ans: coastal areas do not experience much variation in the temperature because it is very close
to the sea.
9. Describe the weather in the Northern part of the country during cold weather season
Ans: The northern part of the country will have the following weather conditions during cold
weather season:
i. Clear sky ii. Low temperature and low humidity iii. Feeble winds
 10. What do you mean by the word Loo?
Ans: The strong, gusty, hot, dry winds blowing during the day over the north and northwestern India is called
Loo.
11. During which month of the year the Retreating monsoon arrives?
a. Mid November to February b. March to May
c. Early June to September d. October - November
12. Kal Bhaisakhi is associated with which state?
a. Panjab b. Odisha c. Karnataka d. West Bengal
13. In which of the following rainfall is least?
a. Gujarat b. Interiors of deccan plateaus c. Leh in Jammu and Kashmir d. Himalayan region
14. Which winds bring widespread rainfall all over the mainland of India
a. North eastern winds b. Sea breeze c. Coastal winds d. South western monsoon winds
15. What is important for the cultivation of rabi crops?
a. Mahawat b. Hail c. Frost d. snow
II Answer the following questions:
1. What are the major controls of the climate? (2)
Ans: The major climatic controls of the earth are as follows:
i. Latitude
ii. Altitude
iii. Pressure and winds
iv. Ocean currents
v. Distance from the sea
vi. Relief features
2. Describe the regional variations in the climatic conditions of India with the help of suitable
examples. (3)
Ans: i. Despite an overall unity in the general pattern, there are perceptible differences in the climatic
conditions. Let's examine this with the two important elements - Temperature and Precipitation.
ii. In summer. mercury occasionally touches 50°C in some parts of Rajasthan dessert. Whereas, It
would be 20°C in pahalgam in Jammu and Kashmir.
iii. In winter, temperature at Drass in J&K will be minus 45°C. Thiruvananthapuram on the other hand,
may have 22°C
iv. There are different kinds of precipitation. The Himalayas may receive snowfall. It rains over the rest
of the country.
v. The annual precipitation varies from 400 cm in Meghalaya to less than 10 cm in Ladakh and
Rajasthan.
3. “The pressure and wind conditions are unique over India”. Justify the statement. (5)
Ans: The pressure and wind conditions over India are unique. These are the reasons:
i. During winter there is a high-pressure area north of the Himalayas. Cold-dry winds blow from this
region to the low-pressure areas over to the south.
ii. In summer, a low-pressure area develops over interior Asia, as well as, over north western India. Thi
causes a complete reversal of the direction of winds during summer. Air moves from a high pressure area over
the southern Indian ocean, in a south-easterly direction, crosses the equator, and turns right towards the
low-pressure areas over the Indian subcontinent.
 iii. These are known as south-west monsoon winds. These winds blow over warm oceans, gather
moisture and bring widespread rainfall over the mainland of India.
4. Explain the factors affecting India’s climate.(5)
Ans: The following are the factors that affect climate in India:
a. Latitude:
i. The tropic of cancer passes through the middle of the country from Rann of Kuch in the west to
Mizoram in the east.
ii. Almost half of the country, lying south of the Tropic of Cancer, belongs to the tropical area. All
the remaining area, north of the Tropic, lies in the sub-tropics.
iii. Therefore, India’s climate has characteristics of tropical as well as subtropical climates.
b. Altitude:
i. India has mountains to the north, which have an average height of about 6,000 metres.
ii. India also has a vast coastal area where the maximum elevation is about 30 metres.
iii. The Himalayas prevent the cold winds from Central Asia from entering the subcontinent. It is
because of these mountains that this subcontinent experiences comparatively milder winters as
compared to central Asia.
c. Pressure and Winds
i. The climate and associated weather conditions in India are governed by the following
atmospheric conditions:
• Pressure and surface winds; • Upper air circulation; and • Western cyclonic disturbances
and tropical cyclones.
ii. India lies in the region of north easterly winds. These winds originate from the subtropical
high-pressure belt of the northern hemisphere.
iii. They blow southwards, get deflected to the right due to the Coriolis force, and move towards the
equatorial low-pressure area
5. Differentiate between the Hot weather season and Cold weather season in India. (5)
Ans: The Hot Weather Season (Summer)
i) From March to May, it is the hot weather season in India. In March, the highest temperature is
about 38° Celsius, recorded on the Deccan plateau. In April, temperatures in Gujarat and Madhya
Pradesh are around 42° Celsius. In May, a temperature of 45° Celsius is common in the northwestern
parts of the country.
ii) A striking feature of the hot weather season is the ‘loo’. These are strong, gusty, hot, dry winds
blowing during the day over the north and north western India. Sometimes they even continue until late
in the evening. Direct exposure to these winds may even prove to be fatal.
iii) Dust storms are very common during the month of May in northern India. These storms bring
temporary relief as they lower the temperature and may bring light rain and cool breeze.
iv) This is also the season for localised thunderstorms, associated with violent winds, torrential
downpours, often accompanied by hail. In West Bengal, these storms are known as the ‘Kaal Baisakhi’
calamity for the month of Baisakh.
v) Towards the close of the summer season, pre-monsoon showers are common especially, in
Kerala and Karnataka. They help in the early ripening of mangoes, and are often referred to as ‘mango
showers’.
The Cold Weather Season (winter)
 i) The cold weather season begins from mid- November in northern India and stays till February.
December and January are the coldest months in the northern part of India. The temperature decreases
from south to north.
ii) The average temperature of Chennai, on the eastern coast, is between 24° - 25° Celsius, while
in the northern plains, it ranges between 10° -15° Celsius. Days are warm and nights are cold. Frost is
common in the north and the higher slopes of the Himalayas experience snowfall.
iii) During this season, the northeast trade winds prevail over the country. They blow from land to
sea and hence, for most parts of the country, it is a dry season. Some amount of rainfall occurs on the
Tamil Nadu coast from these winds as, here they blow from sea to land.
iv) A characteristic feature of the cold weather season over the northern plains is the inflow of
cyclonic disturbances from the west and the northwest. These low-pressure systems originate over the
Mediterranean Sea and western Asia and move into India, along with the westerly flow. They cause the
much-needed winter rains over the plains and snowfall in the mountains. Although the total amount of
winter rainfall locally known as ‘mahawat’ is small, they are of immense importance for the cultivation of
‘rabi’ crops.
6. Differentiate between the South - West Monsoon winds and North- East Monsoon winds
which prevail over our Indian subcontinent. (5)
Ans:
South-west Monsoon winds North Eastern monsoon winds
i. These monsoon winds blow northward from These monsoon winds blow from the northeast
the Arabian sea and the Bay of Bengal. (Central Asia) towards the sea-side.
ii. These monsoon winds blow from June to These winds blow from October to November.
September.
iii. These winds cause country-wide rainfall. These cause rainfall only in Coromandel coast
including Tamil Nadu when these strike at the
wetlands of the Eastern Ghats.
iv. These blow from oceanic high pressure These winds blow from land to sea as a result of
areas towards the low pressure areas of land. reversal in the direction of wind or start of
retreating monsoon season.
v. These winds blow during the advancing These winds blow during the retreating
monsoon season. monsoon season.
7. Write a brief account of the conditions and characteristics of the Advancing monsoons. (5)
Ans: The features of advancing monsoon are given below:
(i) It begins by early June.
(ii) The low-pressure condition over the northern plains attracts the: trade winds of the southern
hemisphere. As these winds blow over warm oceans, they bring abundant moisture to the
subcontinent. (iii) As a result, the windward side of the Western Ghats receives very heavy rainfall, and
the Deccan Plateau and parts of Madhya Pradesh also receive some amount of rain in spite of lying in
the rain shadow area. (iv) The maximum rainfall of this season in the world is received by Mawsynram
in the southern ranges of the Khasi Hills.
(v) Another phenomenon associated with the monsoon is its tendency to have `breaks' in rainfall.
The 'break' in monsoon means the monsoon rains take place only for a few days at a time.
(vi) The monsoon is known for its uncertainties. While it causes heavy floods, in one part, it may be
 responsible for droughts in the other.
8. Write a brief account of the conditions and characteristics of the Retreating monsoons.
Ans: The weather conditions and characteristics of the retreating monsoon are given below:
(i) It falls between October and November.
(ii) It is a period of transition from the hot rainy season to dry winter conditions.
(iii) The withdrawal of the monsoon is marked by clear skies and a rise in temperature.
(iv) Day temperature is high and humid but nights are cool and pleasant. This is commonly known
as 'October heat'.
(v) In the second half of October, the mercury begins to fall rapidly in northern India. The low-pressure
conditions over north-western India, get transferred to the Bay of Bengal by early November due to
occurrence of cyclonic depressions, which originate over the Andaman Sea.
(vi) The delta region of the eastern coast of India is frequently struck by cyclones. The deltas of Godavari,
Krishna and Kaveri are also frequently struck by cyclones which cause great damage to life and property.
(vii) Sometimes, these cyclones arrive at the coasts of Orissa, West Bengal, and Bangladesh. The heavy
rainfall of the Coromandel Coast is due to these depressions and cyclones.
9. “The distribution of Rainfall in India is not uniform”. Support the statement with examples. (5)
Ans: i. Parts of Western coast and north-eastern India receive over about 400 cm
of rainfall annually.
ii. It is less than 60cm in Western Rajasthan and adjoining part of Gujarat,
Haryana and Punjab.
iii. Rainfall is equally low in the interior of the Deccan plateau, and east of the
Sahyadris.
iv. A third area of low precipitation is around Leh in Jammu and Kashmir.
v. The rest of the country receives moderate rainfall
10. Why is Monsoon considered a unifying bond? (5)
Ans: i. The peninsular plateau, under the influence of the sea from three sides, has moderate
temperature. Despite such moderating influences, there are great variations in the temperature
conditions.
ii. Nevertheless, the unifying influence of the monsoon on the Indian subcontinent is quite
perceptible.
iii. The seasonal alteration of the wind systems and the associated weather conditions provide a
rhythmic cycle of seasons. Even the uncertainties of rain and uneven distribution are very much typical
of the monsoons.
iv. The Indian landscape, its animal and plant life, its entire agricultural calendar and the life of
the people, including their festivities, revolve around this phenomenon.
v. Year after year, people of India from north to south and from east to west, eagerly await the
arrival of the monsoon.
vi. These monsoon winds bind the whole country by providing water to set the agricultural
activities in motion.
vii. The river valleys which carry this water also unite as a single river valley unit.