The increasing amount of carbon dioxide in the air is slowly raising the temperature of the atmosphere, because it absorbs
[UPSC Civil Services Exam – 2012 Prelims]
(a) the water vapour of the air and retains its heat
(b) the ultraviolet part of the solar radiation
(c) all the solar radiations
(d) the infrared part of the solar radiation
Answer: (d)
Explanation:
- The increasing amount of carbon dioxide in the air is slowly raising the temperature of the atmosphere because it absorbs the infrared part of the solar radiation. Only water vapour has the ability to absorb both incoming UV and outgoing infrared radiation. Hence option 4 is correct.
- Carbon dioxide strongly absorbs energy with a wavelength of 15 μm (micrometres).
- This makes carbon dioxide a good absorber of wavelengths falling in the infrared radiation region of the spectrum.