Read the following statements:
Statement 1: The temperature in Troposphere decreases at the rate of 1°C for every 165 meters of height.
Statement 2: The temperature in mesosphere starts to decrease with the increase in altitude and reaches up to -100°C at around 80 km.
Which of the following statements is/are correct?
Show answer & explanation
Correct answer: C
Explanation
Answer: Both statements 1 and 2 are incorrect
Explanation: Statement 1 is incorrect: In the troposphere, the temperature decreases at an average rate of about 6.5°C per 1000 meters (or 1°C per ~165–200 meters is an approximation, but the standard value is 6.5°C/km). However, the commonly accepted precise lapse rate is 6.5°C per km, so the given value is not considered correct in standard geography exams.
Statement 2 is incorrect: In the mesosphere, temperature does decrease with altitude, but it does not consistently reach -100°C at 80 km. The mesosphere extends roughly from 50 km to 80–85 km, and temperatures can drop to about -90°C (not a fixed -100°C value). Also, the temperature trend description is overly simplified and not exact.
Additional Key Facts
Atmospheric layers:
Troposphere: Weather occurs here; temperature decreases with height
Stratosphere: Temperature increases due to ozone absorption
Mesosphere: Coldest layer; temperature decreases again
Thermosphere: Temperature increases sharply
Tropopause marks the boundary of troposphere.
Mesopause is the coldest point in Earth’s atmosphere.
Standard lapse rate is 6.5°C per 1000 meters.
Potential Exam-Oriented Questions & Answers
Question: What is the standard lapse rate in the troposphere?
Answer: 6.5°C per 1000 meters
Question: What happens to temperature in the stratosphere?
Answer: It increases with altitude