A senior sustainability consultant at an African think tank explains the complexities of different Earth science systems to a group of ESG practitioners as part of the think tank’s continuing education program.
Which of the following statements by the sustainability consultant accurately describes the Earth’s greenhouse effect?
The Earth's greenhouse effect is a natural process wherein certain gases in the Earth's atmosphere trap and retain heat, thereby warming the planet. While none of the statements perfectly describe this phenomenon, option A is closest by describing a natural process involving the absorption of solar energy. The greenhouse effect involves the Earth's atmosphere absorbing and reradiating infrared radiation, which is akin to absorbing non-reflected incoming solar energy. Thus, option A most accurately describes a component of the natural processes related to the Earth's greenhouse effect.
It is not correct : GH effect is a natural phenomenon where certain gases in the Earth's atmosphere trap and retain heat
None of answers describes the natural process called GH effect. Answer A describes a consquence of the radiative forcing due to increased CO2 / temperature in the atmosphere and is thus probably better than answer D, which is wrong.
The key clue here is GH effect which in 2024 curriculum, Albedo effect is not described as a 'main contributor' from human activities. The answers are all misleading. However, non-reflective energy is absorbed into the ocean and this applies to the natural process and human-driven process.
In section 1.4, p.7 of the curriculum one can read: "Greenhouse gases are a part of the atmo-sphere that absorbs infrared radiation (or radiant heat). In the 1820s, Joseph Fourier recognized that these gases reduced the amount of power the Earth radiated to space, so a planet with more greenhouse gases in the atmosphere must be warmer than one without. This is what scientists mean when they talk about a greenhouse effect." The Albedo effect can amplify warming but it is not the main contributor.
D is undisputed answer
Greenhouse effect is a human driven process. So the answer should be either C or D.
There is no dispute that correct answer is D majority of GH is more human activity induced and is main contributor for decrease in albedo affect as it results in decreased ice cover. Natural GH could not have resulted in exponential warming resulting in reduced ice cover.
All options are incorrect however the answer D is the 'most' appropriate one
all options are incorrect