Question map
Not attempted Correct Incorrect ★ Bookmarked
Loading…
Q119 (NDA-II/2025) Geography › World Physical Geography › Atmospheric structure Answer Verified

Consider the following statements with reference to structure of the Earth's atmosphere : 1. Thickness of the troposphere is greatest at the equator 2. The air temperature of the tropopause is highest above the poles 3. The temperature in troposphere decreases at the rate of 1ºF for every 165 m of height Which of the statements given above is/are correct ?

Result
Your answer: —  ·  Correct: B
Explanation

Statement 1 is correct as the troposphere's thickness is greatest at the equator (18 km) due to intense convective heating and vertical expansion, compared to only 8 km at the poles [3]. Statement 2 is correct because the tropopause temperature is actually higher above the poles (approximately -45°C) than above the equator (approximately -80°C) [5]. This occurs because the greater vertical extent of the troposphere at the equator allows for a longer duration of temperature decline before reaching the tropopause [2]. Statement 3 is incorrect; while the temperature decreases with height, the standard normal lapse rate is 1°C for every 165 m (or 6.5°C per km), not 1°F [5]. Therefore, only statements 1 and 2 are accurate representations of the Earth's atmospheric structure.

Sources

  1. [1] Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 1: BASIC CONCEPTS OF ENVIRONMENT AND ECOLOGY > Structure of the Atmosphere > p. 7
  2. [3] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 20: Earths Atmosphere > Troposphere (0 to 12 km) > p. 274
  3. [2] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 20: Earths Atmosphere > Troposphere (0 to 12 km) > p. 275
  4. [5] https://egyankosh.ac.in/bitstream/123456789/103159/3/Block-2.pdf
How others answered
Each bar shows the % of students who chose that option. Green bar = correct answer, blue outline = your choice.
Community Performance
Out of everyone who attempted this question.
50%
got it right
✓ Thank you! We'll review this.

SIMILAR QUESTIONS

IAS · 2024 · Q2 Relevance score: 5.05

Consider the following statements : Statement-I : Thickness of the troposphere at the equator is much greater as compared to poles. Statement-II : At the equator, heat is transported to great heights by strong convectional currents. Which one of the following is correct in respect of the above statements ?

NDA-II · 2009 · Q39 Relevance score: 2.02

Consider the following statements related to stratification of atmospheric layers: 1. All storms and cloudiness are restricted to stratosphere. 2. Cirrus clouds are formed on the top layers of troposphere. 3. Stratosphere is also an ‘isoclinal layer’. Which of the statements given above are correct ?

CDS-II · 2016 · Q33 Relevance score: 1.82

Which of the following statements concerning atmosphere of the Earth are correct? 1. In stratosphere, temperature increases with altitude. 2. In mesosphere, temperature decreases with altitude. 3. The lowest temperature of the atmosphere is recorded in the upper part of mesosphere. 4. Tropopause is an isothermal zone. Select the correct answer using the code given below.

IAS · 2004 · Q71 Relevance score: 1.34

Assertion (A) : The thickness of the atmosphere is maximum over the Equator. Reason (R) : High insolation and strong convection currents occur over the Equator.