The following item consists of two statements, Statement I and Statement II. Examine these two statements carefully and select the correct answer using the code given below :
Statement I : All the energy received by the earth is from the Sun through electro-magnetic radiation
Statement II : The earth also radiates back all the received energy through various ways to maintain the heat budget of the planet
Both the statements are individually true and Statement II is the correct explanation of Statement I
Both the statements are individually true but Statement II is NOT the correct explanation of Statement I
Statement I is true but Statement II is false
Statement I is false but Statement II is true
Answer is Wrong!
Answer is Right!
This question was previously asked in
UPSC CAPF – 2015
Statement II: The earth also radiates back all the received energy through various ways to maintain the heat budget of the planet. This statement is false as worded. The Earth does radiate energy back into space (primarily infrared radiation) to maintain a thermal balance. However, it does not radiate *all* the received energy. A significant portion of incoming solar radiation (about 30%) is reflected back to space by clouds, aerosols, and the Earth’s surface (this is known as albedo). The Earth absorbs the remaining energy (about 70%) and then radiates an equivalent amount of energy as infrared radiation on average to achieve radiative equilibrium. The statement “all the received energy” is inaccurate because it ignores the reflected portion. Furthermore, the current climate change indicates that the heat budget is currently not perfectly maintained; the Earth is absorbing slightly more energy than it radiates back due to the greenhouse effect.