Correct Option
The correct option is Altitude.
Explanation
Temperature distribution is influenced by several factors, including latitude, altitude, distance from the sea, and ocean currents. Among these, altitude plays a critical role in determining local temperature patterns. In the troposphere, temperature decreases with an increase in elevation, a phenomenon known as the Normal Lapse Rate.
Detailed Analysis
The variation in temperature between Agra and Darjeeling, despite their location on similar latitudes, is explained as follows:
- Altitude: The Normal Lapse Rate states that temperature drops by approximately 6.5°C for every 1,000 meters of ascent. Agra is located in the Indo-Gangetic plains at an elevation of approximately 169 meters above mean sea level. In contrast, Darjeeling is situated in the Himalayas at an elevation of over 2,000 meters. This significant difference in height results in much lower temperatures in Darjeeling compared to Agra.
- Distance from the Sea: While continentality (distance from the sea) affects temperature range, it does not account for the drastic difference in mean monthly temperature between a hill station and a plain city on the same latitude as significantly as altitude does in this context.
- Ocean Currents: These influence coastal regions. Since both Agra and Darjeeling are inland locations, ocean currents are not the primary factor.
- Monsoon Winds: While winds influence weather patterns, the fundamental structural difference causing the permanent temperature disparity between these two specific locations is elevation.
Key Takeaway: Altitude overrides latitude as a climatic control in mountainous regions due to the Normal Lapse Rate, causing hill stations to remain colder than plains situated on the same latitude.