The large amounts of carbon dioxide now being released into the atmosp

Question

The large amounts of carbon dioxide now being released into the atmosphere by the burning of fossil fuels will not, in fact, result in a greenhouse effect—an increase in average global temperatures. Since plants use carbon dioxide in larger quantities if the supply is increased, they are able to grow larger and multiply more vigorously, and atmospheric carbon dioxide concentrations will eventually become stable.

Which of the following, if true, would most seriously weaken the conclusion that a greenhouse effect will not result from the current release of large amounts of carbon dioxide into the atmosphere?

A. The expected rise in average global temperatures has not yet been observed.

B. Ocean waters absorb carbon dioxide at a greater rate when the atmospheric concentration of carbon dioxide is higher.

C. Since the beginning of the industrial Revolution, increased atmospheric concentrations of carbon dioxide have resulted in improved agricultural productivity.

D. When plants decay, they produce methane, another gas that can have a marked greenhouse effect.

E. The fact that carbon dioxide levels have risen and fallen many times in the Earth's history suggests that there is some biological process that can reverse the greenhouse effect

svasan05 · Answer

Pre-thinking:

Conclusion:  More carbon dioxide will not result in greenhouse effect.

Premise on which it is based:  More carbon dioxide will be absorbed by plants to grow larger and multiply more, thereby stabilizing atmospheric concentrations and preventing greenhouse effect.

We need to weaken the conclusion. Hence, we need to look for options which show that more carbon dioxide released into the atmosphere  will  result in greenhouse effect.

Let us examine the answer options:

A. The expected rise in average global temperatures has not yet been observed.  Just because it has not  yet  been observed does not mean it will not happen in the future. Eliminate.

B. Ocean waters absorb carbon dioxide at a greater rate when the atmospheric concentration of carbon dioxide is higher.  If anything, this strengthens the conclusion. If oceans absorb carbon dioxide at a greater rate, then there will be less carbon dioxide in the atmosphere. Eliminate.

C. Since the beginning of the industrial Revolution, increased atmospheric concentrations of carbon dioxide have resulted in improved agricultural productivity.  Agricultural productivity is irrelevant to greenhouse effect of carbon dioxide. Eliminate.

D. When plants decay, they produce methane, another gas that can have a marked greenhouse effect.  Correct answer. More carbon dioxide --> larger and more plants --> larger and more plants die and decay --> more methane --> greenhouse effect.

E. The fact that carbon dioxide levels have risen and fallen many times in the Earth's history suggests that there is some biological process that can reverse the greenhouse effect  The conclusion is about whether there will be greenhouse effect at all and not whether or not it can be reversed. Eliminate.

Hope this helps.

jrk23 · Answer

I have a doubt regarding the explanation of "E" option.

Can't we say that some biological process is responsible for the decrease of Co2 therefore it is acting as a weakener.As some another factor is responsible for it.

Please let me know why this is wrong.

Thanks

Quantum2022 · Answer

I was stuck between B and D but chose B!

My logic was, well if the oceans absorb more C02 then there's less for the plants, less for them to use, so it's bad for the atmosphere overall. The leaps in logic that I made makes me want to cry 😭

Posted from my mobile device

MBAB123 · Answer

Quantum2022 , B is essentially a strengthener, It doesn't matter if plants take care of the CO2 or the ocean takes care of the C02. C02 is being taken care of and hence its release will not result in a green house effect.

MBAB123 · Answer

Hey jrk23  even if another factor is responsible for the decrease in C02, the option becomes a weakener. We're looking for a scenario in which the release of C02  Will  cause greenhouse effects.

svasan05 · Answer

Hi

The "biological" process referred to in option (E) is only responsible for the  reversal  of the greenhouse effect ie; the falling back down of the temperature after it has risen. The conclusion, on the other hand, talks about the greenhouse effect itself, ie; the original increase in temperature. The reversal of the greenhouse effect does not mean that the temperature did not rise at all, or rose lower than expected, which is what is required for the weakening of the conclusion. Therefore option (E) cannot be considered a weakener of the conclusion.

Hope this clarifies.

Hatakekakashi · Answer

Conclusion - No greenhouse effect as more CO2 will allow plants to grow and thus absorb CO2 and everything will be stable

D says that if there are indeed more plants and they decay they release methane which is a greenhouse gas, so if the above is true then this should be true so thus D

VerbalBot · Answer

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The large amounts of carbon dioxide now being released into the atmosp

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The large amounts of carbon dioxide now being released into the atmosp

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