NCERT 9th Class (CBSE) Social Science: Climate

Question: What is Mahawat?

Answer: ‘Mahawat’ is the total amount of rainfall in the cold weather season that is the winter season which is caused by the western cyclonic disturbances in the north and north-western part of India.

Question: What is Coriolis force?

Answer: An apparent force that as a result of the earth’s rotation deflects moving objects (such as projectiles or air currents) to the right in the northern hemisphere and to the left in the southern hemisphere

Question: Give the characteristic features of the not weather season (summer).

Answer: India experiences the hot weather season from the month of March to May. During this season, there is apparent Northward movement of the sun. The hot weather season has the following characteristics.

1. There is overall increase in temperature e.g. the temperature of Northern plains is between 42 – 45°C and in the Deccan plateau between 35 – 38°C.
2. An elongated low-pressure area develops from Thar Desert (in North-West) to Patna and Chota Nagpur plateau (in East and South-East) towards the end of May. From this low-pressure belt, the circulation of air begins.
3. In the Northern and North-Western plain, there is occurrence of ‘Loo’ – strong, hot, dry wind.
4. In the Northern India, there is common occurrence of dust storm in May.
5. There is also occurrence of localized thunderstorms associated with violent winds, torrential downpours, often accompanied by hailstorm at some places (e.g. West Bengal).

Question: What is ‘Kaal Baisakhi‘?

Answer: Violent thunderstorms in the Gangetic plains of India are locally known as Kaal Baisakhi or Nor’westers. These localised events are generally associated with thunderstorms accompanied by strong squally winds and torrential rainfall.