social science of 9th class book Geography climate
Answers
Geography Chapter 4
Climate
Question 1. Choose the correct answer from the four alternatives given below.
(i) Which one of the following places receives the highest rainfall in the world?
(a) Silchar
(b) Mawsynram
(c) Cherrapunji
(d) Guwahati
Answer : (b) Mawsynram
(ii) The wind blowing in the northern plains in summers is known as:
(a) Kaal Baisakhi
(b) Loo
(c) Trade Winds
(d) None of the above
Answer : (b) Loo
(iii) Which one of the following causes rainfall during winters in north-western part of
India.
(a) Cyclonic depression
(b) Retreating monsoon
(c) Western disturbances
(d) Southwest monsoon
Answer :(a) Cyclonic depression
(iv) Monsoon arrives in India approximately in:
(a) Early May
(b) Early July
(c) Early June
(d) Early August
Answer : (c) Early June
(v) Which one of the following characterises the cold weather season in India?
(a) Warm days and warm nights
(b) Warm days and cold nights
(c) Cool days and cold nights
(d) Cold days and warm nights
Answer :(c) Cool days and cold nights
Question 2. Answer the following questions briefly.
(i) What are the factors affecting the climate of India?
Answer: The elements affecting the climate are temperature, atmospheric pressure, wind,
humidity and precipitation.
(ii) Why does India have a monsoon type of climate?
Answer:The monsoon type of climate is characterised by a distinct seasonal pattern. The weather conditions greatly change from one season to the other. These changes are
particularly noticeable in the interior parts of the country. The coastal areas do not
experience much variation in temperature though there is variation in rainfall pattern. Four main seasons can be identified in India – the cold weather season, the hot weather season, the advancing monsoon and the retreating monsoon with some regional variations.
(iii) Which part of India does experience the highest diurnal range of temperature and
why?
Answer : The north-western part of India experiences the highest diurnal range of
temperature. In the Thar desert, the day temperature may rise to 50 0 e and drop down to near 15°e the same night. On the other hand, there is hardly any difference in day and night temperatures in the Andaman and Nicobar Islands or in Kerala .
(iv) Which winds account for rainfall along the Malabar coast?
Answer: Malabar Coast gets rains from depressions and cyclones.
(v) What are Jet streams and how do they affect the climate of India?
Answer : Jet streams are a narrow belt of high altitude (above 12000 m) westerly winds in
the troposphere.
(a) Their speed varies from about 110 km/h in summer to about 184 km/h in winter.
(b) A number of separate jet streams have been identified.
(c) The most constant are the mid latitude and subtropical jet streams.
(d) Jet streams over the Indian peninsula during the summer affect the monsoon.
(e) The subtropical westerly jet stream blow south of the Himalayas and is responsible for
the western cyclonic disturbances experienced in the north and north western parts of the
country.
(f) An easterly jet stream blows over peninsular India. It affects the coastal regions of the
country and is responsible for tropical cyclones during the monsoon as well as during the October to November period.
(vi) Define monsoons. What do you understand by “break” in monsoon?
Answer : Monsoon refers to the seasonal reversal in the wind direction. Monsoon ‘break’
refers to the occurrence of wet and dry spells during the rainy season. The monsoon rains
take place only for a few days at a time.
(vii) Why is the monsoon considered a unifying bond?
Answer : The seasonal alteration of the wind systems and the associated weather conditions provide a rhythmic cycle of seasons. Monsoon rains are unevenly distributed and typically uncertain. The Indian landscape, plant and animal life, agriculture, the people and their festivities, all revolve around the monsoon. All the Indian people eagerly await the arrival of the monsoon. It binds the whole country by providing water which sets all agricultural activities in motion. That is why the monsoon is considered a unifying bond.
Question 3. Why does the rainfall decrease from the east to the west in Northern India.
Answer :Rainfall decreases from the east to the west in Northern India because there is a decrease in the moisture of the winds. As the moisture bearing winds of the Bay of Bengal
branch of the south west monsoon move further and further inland, the moisture gradually decreases and results in low rainfall when moving westwards. Consequently, states like Gujarat and Rajasthan in western India get very little rainfall.
NCERT Solution
Geography Chapter 4
Climate
Question 1. Choose the correct answer from the four alternatives given below.
(i) Which one of the following places receives the highest rainfall in the world?
(a) Silchar
(b) Mawsynram
(c) Cherrapunji
(d) Guwahati
Answer : (b) Mawsynram
(ii) The wind blowing in the northern plains in summers is known as:
(a) Kaal Baisakhi
(b) Loo
(c) Trade Winds
(d) None of the above
Answer : (b) Loo
(iii) Which one of the following causes rainfall during winters in north-western part of
India.
(a) Cyclonic depression
(b) Retreating monsoon
(c) Western disturbances
(d) Southwest monsoon
Answer :(a) Cyclonic depression
(iv) Monsoon arrives in India approximately in:
(a) Early May
(b) Early July
(c) Early June
(d) Early August
Answer : (c) Early June
(v) Which one of the following characterises the cold weather season in India?
(a) Warm days and warm nights
(b) Warm days and cold nights
(c) Cool days and cold nights
(d) Cold days and warm nights
Answer :(c) Cool days and cold nights
Question 2. Answer the following questions briefly.
(i) What are the factors affecting the climate of India?
Answer: The elements affecting the climate are temperature, atmospheric pressure, wind,
humidity and precipitation.
(ii) Why does India have a monsoon type of climate?
Answer:The monsoon type of climate is characterised by a distinct seasonal pattern. The weather conditions greatly change from one season to the other. These changes are
particularly noticeable in the interior parts of the country. The coastal areas do not
experience much variation in temperature though there is variation in rainfall pattern. Four main seasons can be identified in India – the cold weather season, the hot weather season, the advancing monsoon and the retreating monsoon with some regional variations.
(iii) Which part of India does experience the highest diurnal range of temperature and
why?
Answer : The north-western part of India experiences the highest diurnal range of
temperature. In the Thar desert, the day temperature may rise to 50 0 e and drop down to near 15°e the same night. On the other hand, there is hardly any difference in day and night temperatures in the Andaman and Nicobar Islands or in Kerala .
(iv) Which winds account for rainfall along the Malabar coast?
Answer: Malabar Coast gets rains from depressions and cyclones.
(v) What are Jet streams and how do they affect the climate of India?
Answer : Jet streams are a narrow belt of high altitude (above 12000 m) westerly winds in
the troposphere.
(a) Their speed varies from about 110 km/h in summer to about 184 km/h in winter.
(b) A number of separate jet streams have been identified.
(c) The most constant are the mid latitude and subtropical jet streams.
(d) Jet streams over the Indian peninsula during the summer affect the monsoon.
(e) The subtropical westerly jet stream blow south of the Himalayas and is responsible for
the western cyclonic disturbances experienced in the north and north western parts of the
country.
(f) An easterly jet stream blows over peninsular India. It affects the coastal regions of the
country and is responsible for tropical cyclones during the monsoon as well as during the October to November period.
(vi) Define monsoons. What do you understand by “break” in monsoon?
Answer : Monsoon refers to the seasonal reversal in the wind direction. Monsoon ‘break’
refers to the occurrence of wet and dry spells during the rainy season. The monsoon rains
take place only for a few days at a time.
(vii) Why is the monsoon considered a unifying bond?
Answer : The seasonal alteration of the wind systems and the associated weather conditions provide a rhythmic cycle of seasons. Monsoon rains are unevenly distributed and typically uncertain. The Indian landscape, plant and animal life, agriculture, the people and their festivities, all revolve around the monsoon. All the Indian people eagerly await the arrival of the monsoon. It binds the whole country by providing water which sets all agricultural activities in motion. That is why the monsoon is considered a unifying bond.
Question 3. Why does the rainfall decrease from the east to the west in Northern India.
Answer :Rainfall decreases from the east to the west in Northern India because there is a decrease in the moisture of the winds. As the moisture bearing winds of the Bay of Bengal
branch of the south west monsoon move further and further inland, the moisture gradually decreases and results in low rainfall when moving westwards. Consequently, states like Gujarat and Rajasthan in western India get very little rainfall.