Class-9 Geography Chapter-4 Climate

 EVENTS CONVENT HIGH SCHOOL

03/02/2021             Class-9                   SLOT-2
Geography
Chapter-4 climate

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1.Answer the following Questions

Question-1What are the controls affecting the climate of India?

Solution:There are six major controls of the climate of any place. They are:

 1.     Latitude

2.    Altitude

3.    Pressure and wind system

4.    Distance from the sea (continentality)

5.    Ocean currents

6.    Relief features

Question-2Why does India have a monsoon type of climate?

Solution: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 patterns. 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.

 Question-3Which winds account for rainfall along the Malabar Coast?

Solution:Surface winds account for rainfall along the Malabar coast.

 Question-4Define monsoons. What do you understand by “breaks” in monsoon?

Solution:The seasonal reversal in wind direction during a yeat is called the monsoon. Monsoon tends to have ‘breaks’ in rainfall; which means that there are wet and dry spells in between The monsoon rains take place only for a few days at a time and then come to the rainless intervals.

 Question-5Why is the monsoon considered a unifying bond?

Solution:Despite great moderating influences on the climate of India, there are great variations in the temperature conditions. Nevertheless, the unifying influence of the monsoon on the Indian subcontinent is quite perceptible. The seasonal alteration of the wind systems and the associated weather conditions provide a rhythmic cycle of seasons.

 Question-6Why does the rainfall decrease from the east to the west in Northern India?

Solution:The western coast and northeastern India receive over about 400 cm of rainfall annually. However, it is less than 60 cm in western Rajasthan and adjoining parts of Gujarat, Haryana, and Punjab. Rainfall is equally low in the interior of the Deccan plateau, and east of the Sahyadris. The third area of low precipitation is around Leh in Jammu and Kashmir. The rest of the country receives moderate rainfall.

Question-7Give reasons as to why.

(i) The bulk of rainfall in India is concentrated over a few months.

(ii) The Tamil Nadu coast receives winter rainfall.

Solution:(i) The bulk of rainfall in India is concentrated over a few months

The inflow of the south-west monsoon into India brings about a total change in the weather. Early in the season, the windward side of the Western Ghats receives very heavy rainfall, more than 250 cm. The Deccan Plateau and parts of Madhya Pradesh also receive some amount of rain in spite of lying in the rain shadow area. The maximum rainfall of this season is received in the north-eastern part of the country. Mawsynram in the southern ranges of the Khasi Hills receives the highest average rainfall in the world. Rainfall in the Ganga valley decreases from the east to the west. Rajasthan and parts of Gujarat get scanty rainfall.

  (ii) The Tamil Nadu coast receives winter rainfall

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. The peninsular region does not have a well-defined cold season. There is hardly any noticeable seasonal change in temperature patterns during winters due to the moderating influence of the sea.

  Question-8Describe the regional variations in the climatic conditions of India with the help of suitable examples.

Solution:Despite an overall unity in the general pattern, there are perceptible regional variations in climatic conditions within the country. The two important elements, which cause these variations, are – temperature and precipitation.

For example, in summer, the mercury occasionally touches 50°C in some parts of the Rajasthan desert, whereas it may be around 20°C in Pahalgam in Jammu and Kashmir. On a winter night, the temperature at Drass in Jammu and Kashmir may be as low as minus 45°C. Tiruvananthapuram, on the other hand, may have a temperature of 20°C.

Question-9 Discuss the mechanism of monsoons.

Solution:To understand the mechanism of the monsoons, the following facts are important.

The differential heating and cooling of land and water create a low pressure on the landmass of India while the seas around experience comparatively high pressure.

The shift of the position of Inter-Tropical Convergence Zone (ITCZ) in summer, over the Ganga plain (this is the equatorial trough normally positioned about 5°N of the equator – also known as the monsoon trough during the monsoon season).

The presence of the high-pressure area, east of Madagascar, approximately 20°S over the Indian Ocean. The intensity and position of this high-pressure area affect the Indian Monsoon.