Question

The rain shadow effect is used to describe rainfall around certain mountain ranges. Choose the correct statement.
A. The northern hemisphere and the southern hemisphere have the same prevailing winds
B. Cool air can hold more moisture than warm air
C. In the northern hemisphere, there is more rainfall in the eastern slopes
D. You would expect desserts to form on the western side of mountain ranges in the northern hemisphere
E. None of the above

Answer 1

Hint:The word rain shadow refers to land or an area that has been forced to become a dessert. It is characterized as a dry area that is present on the leeward side of a mountainous area. The mountainous area blocks the passage of the rainy weather to the other side of the mountain and thus the area becomes dry and desert due to absence of the rainfall.

Complete answer: Due to the presence of mountains, very little precipitation is seen in rain shadow areas. The mountains act as a barrier and thus blocks the wind and cause the prevailing winds to lose their moisture on the windward side of the mountain ranges. This causes the leeward side of the mountains to become dry. Thus, the rain shadow effect is responsible for the cause of rains on one side of the mountain and the formation of the desert on the other side of the mountain. The trade winds which are also called prevailing winds are located 30 degrees North and 30 degree south latitudes. The trade winds travel from the northeast to the northern hemisphere and from southeast to the southern hemisphere. The westerly winds are opposite to that of the trade winds. These winds originate from the southwest in the Northern hemisphere and in the southern hemisphere they originate from the northwest region. Therefore, all the options provided above are wrong.

So, option E is the correct option.

Note: Example of one such rain shadow area in India is Chennai which lies at the leeward side of the western ghats for the branch of the Arabian Sea. Wind and moisture are the two main factors responsible for the cause of the rain shadow effect. The wind with less moisture content in the area causes the rain shadow effect.