Udhagamandalam (Ooty) and Coimbatore are almost at the same latitude. The range of summer temperatures in Ooty is 10–25° while that in Coimbatore is 25–38°. Why do you think there is such a difference in temperature between these two places?
The significant temperature difference between Ooty and Coimbatore, despite being at almost the same latitude, is due to altitude.
Ooty is a hill station located at a much higher altitude than Coimbatore. As altitude increases, atmospheric pressure and air density decrease, causing the temperature to drop.
Additionally, places farther from the Earth's surface receive less heat because the Sun heats the Earth's surface, and the air gets cooler with distance from this heat source.
This is why Ooty has cooler summers (10-25°C) compared to Coimbatore (25-38°C), which lies in the plains below.
Explanation
The chapter explains on Pages 6-7 that hill stations like Ooty are cooler because of their altitude. Temperature decreases as altitude increases due to two reasons: (1) atmospheric pressure and air density decrease with altitude, making air cooler; (2) the Sun heats the Earth's surface, so places farther from the surface are less hot. Ooty and Coimbatore are used as an example to illustrate this principle.
Solution Steps
Ooty and Coimbatore are at almost the same latitude
The temperature difference is caused by difference in altitude
Ooty is a hill station at much higher altitude than Coimbatore
As altitude increases, atmospheric pressure and air density decrease, causing temperature to drop
The Sun heats the Earth's surface, so places farther from the surface receive less heat