Civil Services Prep

Prelims 2012 · Environment · Question 62

The increasing amount of carbon dioxide in the air is slowly raising the temperature of the atmosphere, because it absorbs

  1. The water vapour of the air and retains its heat.
  2. The ultraviolet part of the solar radiation.
  3. All the solar radiations.
  4. The infrared part of the solar radiation.

Answer

The infrared part of the solar radiation.

  • (a) Incorrect. Carbon dioxide does not warm the atmosphere by absorbing water vapour; rather, it absorbs outgoing infrared (longwave) radiation and re-radiates heat.
  • (b) Incorrect. Ultraviolet radiation is mainly absorbed by ozone in the stratosphere, not by carbon dioxide.
  • (c) Incorrect. Carbon dioxide does not absorb all solar radiation; most incoming shortwave solar radiation passes through the atmosphere.
  • (d) Correct. Carbon dioxide is a greenhouse gas because it absorbs the infrared part of radiation emitted by the Earth, thereby raising atmospheric temperature.
  1. Consider the following statements with reference to India's response to climate change : I. India's Long-Term…
  2. With respect to the Western Hoolock Gibbons, which of the following statements is/are correct? 1. A Sanctuary…
  3. Which of the following best explain(s) the rationale for protecting mangrove ecosystems in the context of…
  4. Which of the following statements with regard to the arrival of Amur Falcons at Doyang Lake in Nagaland each…
  5. With reference to Madhav National Park, which of the following statements is/are correct ? 1. It was declared…
  6. Consider the following statements about Rhynchostylis retusa (Foxtail orchid) : 1. It is an epiphytic orchid.…