With reference to the Earth's atmosphere, which one of the following statements is correct?
AThe total amount of insolation received at the equator is roughly about 10 times of that received at the poles.
BInfrared rays constitute roughly two-thirds of insolation.
CInfrared waves are largely absorbed by water vapour that is concentrated in the lower atmosphere.
DInfrared waves are a part of visible spectrum of electromagnetic waves of solar radiation.
Answer & Solution
Correct answer: C. Infrared waves are largely absorbed by water vapour that is concentrated in the lower atmosphere.
Answer: C. Infrared waves are largely absorbed by water vapour concentrated in the lower atmosphere.
The atmosphere preferentially absorbs LONG-WAVE INFRARED RADIATION while letting short-wave solar radiation pass through. Water vapour (H2O), which is concentrated in the lower troposphere, is the most abundant natural greenhouse gas and is an excellent absorber of infrared radiation in several wavelength bands. CO2 and methane are also IR absorbers but water vapour dominates in atmospheric IR absorption. This is the foundation of the natural greenhouse effect.
Distractors fail:
(A) Equator receives only about 2.5 times the insolation of poles (not 10 times) due to the cosine effect on solar angle.
(B) Infrared is roughly half (45-50%) of solar insolation, not two-thirds.
(D) Infrared waves are NOT part of the visible spectrum. Visible light is between violet and red (400-700 nm); infrared is beyond red (700 nm onwards).
Source: NCERT Class 11 Fundamentals of Physical Geography Ch 9 (Solar Radiation, Heat Balance and Temperature).
Related questions
Which of the following plays an important role in causing rainfall?The Black soil of India is also known as ____ soil.Which Indian state is the world's largest producer of the golden 'Muga' silk?Which wildlife sanctuary was declared the first national park in India?Which one of the following communities is an African community?Which type of forest is found in the Ganga-Brahmaputra delta?On the equinoxes, which of the following occurs?The Bhopal disaster of 1984 was the result of which kind of accident?