General Instruction:
All Questions are Compulsory.
Question No. 1 to 4 carries one mark each.
Question No. 5 to 10 carry three marks each.
Question No. 11 and 12 carry five marks each.
- What does ITCZ means?
- What is Southern Oscillation?
- What is El Nino?
- When does the monsoon withdraw from the Northern half of the peninsula?
- What do you mean by Coriolis force?
- What are jet streams?
- What is ITCZ?
- What is El Nino?
- What is Burst of the monsoon?
- Name the four seasons of India.
- What are the features of Monsoon?
- How do Jet Streams influence the climate of India?
CBSE TEST PAPER-03
Class –IX Social Science (Climate)
[ANSWERS]
1) Inter-Tropical Convergence Zone is the area encircling the earth near the equator where the northeast and southeast trade winds come together.
2) It is a periodic change in pressure conditions i.e. shifting of the air pressure between the Tropical Eastern Pacific Ocean and the Eastern Indian ocean.
3) It is a Spanish word that means the child. It is the name of warm water current which is the temporary replacement of the cold Peruvian current flowing past the Peruvian Coast.
4) By Mid October the monsoon withdraws from the Northern half of the peninsula.
5) a) An apparent force caused by the earth’s rotation.
b) Coriolis force is responsible for deflecting winds towards the right in the northern hemisphere and towards the left in the southern hemisphere.
c) This is also known as Ferrel’s Law.
6) a) These are a narrow belt of high altitude (Above 12000 meters) westerly winds in the troposphere. These winds are found in the Tropopause which is the transition between troposphere and stratosphere.
b) Their speed varies from about 110 km per hour in summer to about 184 km per hour in winter.
c) A number of separate Jet streams have been identified.
d) The most constant is Mid-latitude, the Subtropical, and the Polar Jet streams which are the strongest of all.
7) a) The inter Tropical Convergence Zone is a broad trough of low pressure in equatorial latitudes.
b) This is where the Northeast and the Southeast trade winds converge. When the ITCZ is positioned north or south of the equator, these directions change according to the Coriolis effect imparted by the rotation of the earth.
c) This convergence zone lies more or less parallel to the equator but moves North or South with the apparent movement of the sun.
8) a) This is the name given to the periodic development of a warm ocean current along the coast of Peru as a temporary replacement of the cold Peruvian current.
b) ‘El Nino’ is a Spanish word meaning ‘the child’, and refers to the baby Christ, as this current starts flowing during Christmas.
c) The presence of the El Nino leads to an increase in sea surface temperature and weakening of the trade winds in the region and causes heavy rainfall, floods, or droughts in different regions of the world.
9) a) The monsoon starts in early June in India.
b) At the arrival of the monsoon, the normal rainfall becomes heavy rainfall and continues for many days.
c) This sudden increase in rainfall is termed as the ‘Burst of the monsoon’.
10) a) The hot weather season. (March to May). The influence of shifting of the heat belt can be seen clearly from temperature recordings taken during March-May at different latitudes.
b) Advancing Monsoon season-Rainy season(June to September). Parts of the western coast and northern India receive over about 400 cm of rainfall annually.
c) The Retreating monsoon season (October to November). The low-pressure conditions, over north-western India, get transferred to the Bay of Bengal by early November. This shift is associated with the occurrence of cyclonic depressions, which originate over the Andaman Sea.
d) The cold weather season (December to February). 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 the south to the north.
11) a) The monsoons, unlike the trade winds, are not steady winds but are pulsating in nature.
b) The duration of the monsoon is between 100-120 days from early June to mid-September.
c) Around the time of its arrival the normal rainfall increases suddenly and continues constantly for several days. This is called the ‘Burst of the monsoon’.
d) The monsoon arrives at the southern tip of the India Peninsula generally by the first week of June.
e) It has two branches- the Arabian Sea branch and the Bay of Bengal branch.
f) Because of the nature of monsoons, the annual rainfall is highly variable from year to year. Variability is high in the regions of low rainfall such as parts of Rajasthan, Gujarat, and the leeward (rain shadow area) side of the Western Ghats. While the areas of high rainfall are responsible to be affected by the floods and the areas of low rainfall are drought-prone.
12) a) The westerly flow dominates the upper air circulation. These Jet Streams are known as Subtropical Westerly Jet Streams.
b) Jet streams are located approximately over 27°-30° North latitude.
c) These Jet streams blow south of the Himalayas’ over India throughout the year except in summer.
d) The North and Northwest parts of the country experience the western cyclonic disturbances which are brought in by this westerly flow.
e) In summer the subtropical westerly Jet streams move north of the Himalayas with the apparent movement of the sun.
f) The tropical easterly Jet Streams flows over peninsular India, approximately over 14° North during the summer months
