Environmental Geography

The southwestern monsoon winds bring moisture from the Arabian Sea. As these winds reach the Western Ghats, they are forced to rise, cooling as they ascend. As the air cools, it loses its moisture in the form of rain. This process, known as orographic rainfall, causes the windward side of the Western Ghats to receive heavy rainfall. However, the leeward side, which is Tamil Nadu, is shielded from this moisture.

Step 1: The Rain Shadow Effect
Tamil Nadu is located on the leeward side of the Western Ghats, which causes it to be in the rain shadow region. The rain shadow effect occurs when moisture-laden winds from the ocean rise over mountains, lose moisture as rain on the windward side, and cause dry conditions on the leeward side. This is why the state receives very little rainfall during the southwest monsoon.

Step 2: Impact on Tamil Nadu
While the coastal areas of Tamil Nadu receive some rainfall from the monsoon, the rest of the state experiences dry conditions. The leeward side of the mountains (where Tamil Nadu lies) has significantly less rainfall because the moisture from the monsoon winds has already been deposited on the windward side. As a result, the amount of rainfall received by Tamil Nadu is low compared to other regions in India.

Step 3: Conclusion
Therefore, Tamil Nadu receives low rainfall because it is located in the rain shadow area of the Western Ghats, where the moisture from the southwest monsoon winds does not reach.

Final Answer: due to location in rain shadow area.

Step 1: Understanding Steppes.
Steppes are vast, treeless plains found in temperate climates. They are characterized by grasses and herbaceous plants. The term "steppe" typically refers to temperate grasslands, particularly those found in parts of Eurasia.

Step 2: Explanation of options.
- (A) Tropical grass lands: Tropical grasslands, also known as savannas, are found in tropical regions and are not the same as steppes.
- (B) Temperate grass lands: This is the correct answer. Steppes are a type of temperate grassland.
- (C) Tropical deciduous forests: These forests are found in tropical areas and are not related to the steppe biome.
- (D) Temperate evergreen forests: These forests are found in temperate regions, but they are characterized by evergreen trees, unlike the grassy steppe regions.

Step 3: Conclusion.
Therefore, the correct answer is temperate grasslands, as steppes are a type of temperate grassland.

Final Answer: Temperate grass lands.