[Mission 2024] STATIC QUIZ, 11 August 2023 – Geography

Solution: d)

The monsoons are experienced in the tropical area roughly between 20° N and 20° S. To understand the mechanism of the monsoons, the following facts are important.

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

(b) 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).

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

(d) The Tibetan plateau gets intensely heated during summer, which results in strong vertical air currents and the formation of high pressure over the plateau at about 9 km above sea level.

(e) The movement of the westerly jet stream to the north of the Himalayas and the presence of the tropical easterly jet stream over the Indian peninsula during summer.

Solution: c)

Due to a low temperature in the winter season, a high pressure develops over north-western India.

In contrast to it, low pressure is found over south India, Arabian Sea and Bay of Bengal.

Therefore, winds blow from north-west to south-east.

Solution: b)

Tropical Wet and Dry Climate (Aw): It is found to the north and south of the Amazon forest in Brazil and adjoining parts of Bolivia and Paraguay in South America, Sudan and south of Central Africa. The annual rainfall in this climate is considerably less and is variable also. The wet season is shorter and the dry season is longer with the drought being more severe. Temperature is high throughout the year and diurnal ranges of temperature are the greatest in the dry season. Deciduous forest and tree-shredded grasslands occur in this climate.

Solution: a)

Steppe climate will have lower and irregular rainfall. North-eastern India receives either abundant rainfall or gets too cold for being called a steppe climate.

Solution: c)

Jet streams are some of the strongest winds in the atmosphere. Their speeds usually range from 129 to 225 kilometers per hour, but they can reach more than 443 kilometers per hour. They are faster in winter when the temperature differences between tropical, temperate, and polar air currents are greater.

At most times in the Northern and Southern Hemispheres, there are two jet streams: a subtropical jet stream centered at about 30 degrees latitude and a polar-front jet stream whose position varies with the boundary between polar and temperate air. A reverse jet stream blows toward the west in tropical high altitudes during the Northern Hemispheres summer. It is associated with the heating of the Asian continent and may help bring summer monsoons to the Indian Ocean.