D:Atmospheric Environments

Question 1

2 seasonal changes that result in the monsoon

Answer 1

Migration of the ITCZ, leading to changes in the trade winds

-Differential heating of land and sea

Question 2

Explain how the movement of the ITCZ effects the monsoon

Answer 2

1. The ITCZ is the point where the winds from the N and S hemisphere meet and ascend. Its the point of max cloud and heavy rainfall
2. In the summer seasons the ITCZ shifts Northward as the sun shines over the Tropic of Cancer
3. The SE trade winds cross the equator and bend right due to the Coriolis effect to become SW trade winds
4. This trade winds blow over India, where these winds meet the NE trade winds, the monsoon front occurs, rainfall occurs along this front.

Question 3

How does differential heating of land and sea bring the rainy season

Answer 3

Differential heating of land and sea initiates pressure differences, land masses heat and cool more rapidly and at greater extremes than the seas

1. In the summer intense heating of Asia results in low pressure developing
2. High pressure develops over the sub-tropics, south of the equator
3. Winds blow from the sub-tropical high pressure to the low pressure
4. The winds blow from the SE but after crossing the equator they are deflected right by the Coriolis effect and blow as SW wind across India

Question 4

What/When are the different monsoon seasons

Answer 4

Hot, Rainy Season= June-September
Cool-Dry Season=October-February
Hot-Dry Season= February-May

Question 5

What are the 3 mountain ranges that effect the monsoon

Answer 5

• Western Ghats
• Himalayas
• Eastern Ghats

Question 6

How do the Western Ghats effect the monsoon

Answer 6

They are the first high land that the SW monsoon winds encounter. They rise abruptly from the sub-continent making an effective orographic barrier for the monsoon winds

Question 7

What is orographic uplift

Answer 7

Orographic lift occurs when an air mass is forced from a low elevation to a higher elevation as it moves over rising terrain. As the air mass gains altitude it quickly cools down adiabatically, which can raise the relative humidity to 100% and create clouds and, under the right conditions, precipitation.

Question 8

How do the Himalayas effect the monsoon

Answer 8

They provide a barrier for the wet SW monsoon winds, as they block cold winds from the North allowing the SW monsoon to move Northwards unhindered. It also confines the SW monsoon winds to the subcontinent

Question 9

What are the 4 issues of the monsoon to countries in its path (SRVF)

Answer 9

1. Seasonal Changes- the amount of rainfall varies year to year
2. Unreliable nature of Monsoons, rains are often unreliable and late
3. Risk of Flooding, often monsoon rains coincide with high river levels
4. Variability in Space and Time- great spatial differences within India