At the present time, 98% of the world energy consumption comes from st

Question

At the present time, 98% of the world energy consumption comes from stored sources, such as fossil fuels or nuclear fuel. Only hydroelectric and wood energy represent completely renewable sources on ordinary time scales. Discovery of large additional fossil fuel reserves, solution of the nuclear safety and waste disposal problems, or the development of controlled thermonuclear fusion will provide only a short-term solution to the world’s energy crisis. Within about 100 years, the thermal pollution resulting from our increased energy consumption will make solar energy a necessity at any cost.

Man’s energy consumption is currently about one part in ten thousand that of the energy we receive from the sun. However, it is growing at a 5% rate, of which about 2% represents a population growth and 3% a per capita energy increase. If this growth continues, within 100 years our energy consumption will be about 1 percent of the absorbed solar energy, enough to increase the average temperature of the earth by about one degree centigrade if stored energy continues to be our predominant source. This will be the point at which there will be significant effects in our climate, including the melting of the polar ice caps, a phenomenon that will raise the level of the oceans and flood parts of our major cities. There is positive feedback associated with this process, since the polar ice cap contributes to the partial reflectivity of the energy arriving from the sun: As the ice caps begin to melt, the reflectivity will decrease, thus heating the earth still further.

It is often stated that the growth rate will decline or that energy conservation measures will preclude any long-range problem. Instead, this only postpones the problem by a few years. Conservation by a factor of 2, together with a maintenance of the 5% growth rate, delays the problem by only 14 years. Reduction of the growth rate to 4% postpones the problem by only 25 years; in addition, the inequities in standards of living throughout the world will provide pressure toward an increase in growth rate, particularly if cheap energy is available. The problem of a changing climate will not be evident until perhaps 10 years before it becomes critical due to the nature of an exponential growth rate together with the normal annual weather variations. This may be too short a period to circumvent the problem by converting to other energy sources, so advance planning is a necessity.

The only practical means of avoiding the problem of thermal pollution appears to be the use of solar energy. (Schemes to “air-condition” the earth do not appear to be feasible before the twenty-second century.) Using the solar energy before it is dissipated to heat does not increase the earth’s energy balance. The cost of solar energy is extremely favorable now, particularly when compared to the cost of relocating many of our major cities.   1 
 1. The author is primarily concerned with

(A) describing a phenomenon and explaining its causes
(B) outlining a position and supporting it with statistics
(C) isolating an ambiguity and clarifying it by definition
(D) presenting a problem and advocating a solution for it
(E) citing a counterargument and refuting it

2 
 2. According to the passage, all of the following are factors which will tend to increase thermal pollution EXCEPT

(A) the earth’s increasing population
(B) melting of the polar ice caps
(C) increase in per capita energy consumption
(D) pressure to redress standard of living inequities by increasing energy consumption
(E) expected anomalies in weather patterns

3 
 3. The positive feedback mentioned in means that the melting of the polar ice caps will

(A) reduce per capita energy consumption
(B) accelerate the transition to solar energy
(C) intensify the effects of thermal pollution
(D) necessitate a shift to alternative energy sources
(E) result in the inundations of major cities

4 
 4. The author mentions the possibility of energy conservation in order to

(A) preempt and refute a possible objection to his position
(B) support directly the central thesis of the passage
(C) minimize the significance of a contradiction in the passage
(D) prove that such measures are ineffective and counterproductive
(E) supply the reader with additional background information

5 
 5. It can be inferred that the “airconditioning” of the earth refers to proposals to

(A) distribute frigid air from the polar ice caps to coastal cities as the temperature increases due to thermal pollution
(B) dissipate the surplus of the release of stored solar energy over absorbed solar energy into space
(C) conserve completely renewable energy sources by requiring that industry replace these resources
(D) avoid further thermal pollution by converting to solar energy as opposed to conventional and nuclear sources
(E) utilize hydroelectric and wood energy to replace nonconventional energy sources such as nuclear energy

6 
 6. The tone of the passage is best describe as one of

(A) unmitigated outrage
(B) cautious optimism
(C) reckless abandon
(D) smug self-assurance
(E) pronounced alarm

7 
 7. Which of the following would be the most logical topic for the author to address in a succeeding paragraph?

(A) The problems of nuclear safety and waste disposal
(B) A history of the development of solar energy
(C) The availability and cost of solar energy technology
(D) The practical effects of flooding of coastal cities
(E) The feasibility of geothermal energy

Source:   Master GMAT  
Difficulty Level:   700

Gladiator59 · Accepted Answer

7 mins 41 secs... Got 6 out of 7. Great passage and great questions. Very challenging yet somehow doable.

Will post my thoughts on individual solutions in an edit to this post.

Edit 1:

Summary/Main point: Author is optimistic that starting to convert to solar from conventional energy can help us solve the thermal pollution problem. Lots of info about positive feedback loop.. effects of excess heat and why conservation is no good as it will only delay but not solve the problem is presented by the author.

need to understand the main point of the passage to tackle this.
1. The author is primarily concerned with

(A) describing a phenomenon and explaining its causes TRAP - if the thermal pollution was the phenomenon then author just does not explain causes but goes ahead and talks a lot about solution as well. Discard
(B) outlining a position and supporting it with statistics Discard. Too vague and does not capture the central idea.
(C) isolating an ambiguity and clarifying it by definitionThere is no ambiguity. Discard
(D) presenting a problem and advocating a solution for itPerfect. The author does exactly this.
(E) citing a counterargument and refuting itBS option. Discard.

Detail question. Pretty straightforward as it is mentioned verbatim in the passage
2. According to the passage, all of the following are factors which will tend to increase thermal pollution EXCEPT

(A) the earth’s increasing populationYep. The population growth part
(B) melting of the polar ice caps TRAP - this is both the result of and also a cause of... Refer to positive feedback process.
(C) increase in per capita energy consumptionYep. This is the per capita increment part leading to more demand overall .
(D) pressure to redress standard of living inequities by increasing energy consumptionyep.. me tioned in the passage that such inequalities speed up the growth of energy demand as energy becomes cheap
(E) expected anomalies in weather patternsBingo - this is a pure effect of increase in thermal pollution

Detail question. Positive feedback is explained in melting of icecaps.. which is a result of thermal pollution causes less reflection of suns rays leading to more melting.. like a positive feedback loop
3. The positive feedback mentioned in means that the melting of the polar ice caps will

(A) reduce per capita energy consumption BS option. Discard
(B) accelerate the transition to solar energyBS option. discard
(C) intensify the effects of thermal pollution BINGO! Exactly mentioned in passage
(D) necessitate a shift to alternative energy sourcesTRAP - vague indirect result of this.. but not explaining what it does directly.
(E) result in the inundations of major cities discard... Does mention about submergence of costal areas but the option is vague...

Interesting question. This feels like a CR inside a RC passage. The position of the statement comes right after conservation of energy alternative is introduced only to point out that conservation is a temporary solution unlike what it's proponents convey. Hence it is a counterpoint to it.
4. The author mentions the possibility of energy conservation in order to

(A) preempt and refute a possible objection to his position Bingo! You beauty..
(B) support directly the central thesis of the passage opposite.. discard.
(C) minimize the significance of a contradiction in the passagethere is no contradiction in the passage
(D) prove that such measures are ineffective and counterproductiveTRAP #1: this may be true but this is not the purpose of the statement as used by the author. Need to think from a CR point of view here... This is a classic real world trap.
(E) supply the reader with additional background informationtoo vague. Discard.

Q5 - Didn't get this one.. will add explanation in an edit if I find one or come up with new ideas.

easiest of the lot. Pretty straightforward if you understand the main point
6. The tone of the passage is best describe as one of

(A) unmitigated outrageBS option discard
(B) cautious optimismBingo! The author wants to caution about the evils of current way of life and it's draw back while showing that solar energy ( shifting to it right away) will solve the problem.
(C) reckless abandon discard
(D) smug self-assuranceBS option. Almost an insult to your intellect
(E) pronounced alarm TRAP - this may seem the case if you focus only on the first half of the passage... Overall this is not the time as it is too extreme keeping in light the way the author ends the passage

Follow up passage question . I always mix up these but here it is pretty straightforward due to options and the last sentence of passage
7. Which of the following would be the most logical topic for the author to address in a succeeding paragraph?

(A) The problems of nuclear safety and waste disposal irrelevant to discussion. Discard
(B) A history of the development of solar energy Trap - eventgoughwe are looking for solar energy .. history would be irrelevant to the discussion... Which talks about next steps
(C) The availability and cost of solar energy technologyBingo! Perfect cohesion with the last part which talks about costs etc..
(D) The practical effects of flooding of coastal citiesBS option. Almost one the verge of insane.
(E) The feasibility of geothermal energyalso a plausible candidate .. but discard as the author mentions that "solar is the only way forward" so it is likely that he would talk about next steps with solar in mind

Phew! That was one helluva passage and writing this post took me around 30+ mins... Hope you liked it. Let me know.

Best,
Gladi

easiest of the lot. Pretty straightforward if you understand the main point 6. The tone of the passage is best describe as one of (A) unmitigated outrage BS option discard (B) cautious optimism Bingo! The author wants to caution about the evils of current way of life and it's draw back while showing that solar energy ( shifting to it right away) will solve the problem. (C) reckless abandon discard (D) smug self-assurance BS option. Almost an insult to your intellect (E) pronounced alarm TRAP - this may seem the case if you focus only on the first half of the passage... Overall this is not the time as it is too extreme keeping in light the way the author ends the passage Follow up passage question . I always mix up these but here it is pretty straightforward due to options and the last sentence of passage 7. Which of the following would be the most logical topic for the author to address in a succeeding paragraph? (A) The problems of nuclear safety and waste disposal irrelevant to discussion. Discard (B) A history of the development of solar energy Trap - eventgoughwe are looking for solar energy .. history would be irrelevant to the discussion... Which talks about next steps (C) The availability and cost of solar energy technology Bingo! Perfect cohesion with the last part which talks about costs etc.. (D) The practical effects of flooding of coastal cities BS option. Almost one the verge of insane. (E) The feasibility of geothermal energy also a plausible candidate .. but discard as the author mentions that "solar is the only way forward" so it is likely that he would talk about next steps with solar in mind Phew! That was one helluva passage and writing this post took me around 30+ mins... Hope you liked it. Let me know. Best, Gladi

NinetyFour · Answer

For Q4, can someone explain how the answer is A? I selected D because the following sentence in the passage says "Instead, this only postpones the problem by a few years" This sounds like the "energy conservation" mentioned in the previous sentence will be ineffective.

For Q5, how do we know the answer is B from the passage?

For Q6, I heavily believe the tone is more aligned with "pronounced alarm" than "cautious optimism". The entire passage basically states why we need to move away from energy sources that heat up the earth... Could someone please explain this?

souvikgmat1990 · Answer

I have the same set of questions. Anybody coming up with the explanations would be great.

2asc · Answer

Q4 asks for the authors intentions of mentioning conservation. Yes, the point is to prove that conservation is inefficient in the long run, but the motive of explaining this methodology is to dismiss it as a potential objection to his argument.

Q5 is a bit ambiguous, but think about how a split pack air conditioner works. Without getting too much into the technicalities, we know that it releases cold air inside, and pushes out hot air outside. (B) can be inferred from this analogy.

Confused about Q6 as well.

auradediligodo · Answer

Hello everyone,

Got 4/7 correct in 10:20 minutes, including 4 minutes to read and 6:20 minutes to answer the questions.

---------------------------------------------------------------------------------------------------------------

P1

In the first paragraph the author discusses what are the current short term solutions for saving the climate and then suggests that the only long term solution be solar energy.

Purpose:  To suggest that solar energy be the only solution to save the climate

P2

In this paragraph the author discusses factors related to the increase in temperature.

Purpose:  To discuss factors affecting the increase of temperatures

P3

In this paragraph the author cites a point of view that could be used against her. Then the author proceeds by discarding such point of view and highlight the necessity of advance planning

Purpose:   To discard an objection and suggest benefits for advanced planning

P4

Here the author suggests again that solar energy is the only viable solution and that right now it is also economically convenient.

Main point

To suggest that only solar energy is a cure to our problems and that other solutions would be viable only in the short term

1. The author is primarily concerned with

Pre-thinking

Main point question

To suggest that only solar energy is a cure to our problems and that other solutions would be viable only in the short term

(A) describing a phenomenon and explaining its causes
(B) outlining a position and supporting it with statistics
(C) isolating an ambiguity and clarifying it by definition
  (D)   presenting a problem and advocating a solution for it
(E) citing a counterargument and refuting it

2. According to the passage, all of the following are factors which will tend to increase thermal pollution EXCEPT

Pre-thinking

Detail question

Let's evaluate the options

(A) the earth’s increasing population
 Mentioned here:
  However, it is growing at a 5% rate, of which about 2% represents a population growth and 3% a per capita energy increase.  
(B) melting of the polar ice caps
 Mentioned here:
   As the ice caps begin to melt, the reflectivity will decrease, thus heating the earth still further.    
(C) increase in per capita energy consumption
 Mentioned here:
  If this growth continues, within 100 years our energy consumption will be about 1 percent of the absorbed solar energy, enough to increase the average temperature of the earth    
(D) pressure to redress standard of living inequities by increasing energy consumption
 Mentioned here:
  in addition, the inequities in standards of living throughout the world will provide pressure toward an increase in growth rate,    
  (E)   expected anomalies in weather patterns
 Correct. Such detail is mentioned in another context.

3. The positive feedback mentioned means that the melting of the polar ice caps will

Pre-thinking

Inference question

From P2: 
  There is positive feedback associated with this process, since the polar ice cap contributes to the partial reflectivity of the energy arriving from the sun: As the ice caps begin to melt, the reflectivity will decrease, thus heating the earth still further.

(A) reduce per capita energy consumption
(B) accelerate the transition to solar energy
  (C)   intensify the effects of thermal pollution
(D) necessitate a shift to alternative energy sources
(E) result in the inundations of major cities

4. The author mentions the possibility of energy conservation in order to

Pre-thinking

Purpose question

Energy conservation is mentioned in paragraph 3. As mentioned above the author cites it as a possible objection to her argument. Then the author proceeds by disputing such claim.

(A)   preempt and refute a possible objection to his position
(B) support directly the central thesis of the passage
(C) minimize the significance of a contradiction in the passage
(D) prove that such measures are ineffective and counterproductive
(E) supply the reader with additional background information

5. It can be inferred that the “airconditioning” of the earth refers to proposals to

Pre-thinking

Inference question

From last paragraph:
  (Schemes to “air-condition” the earth do not appear to be feasible before the twenty-second century.)  Using the solar energy before it is dissipated to heat does not increase the earth’s energy balance.

(A) distribute frigid air from the polar ice caps to coastal cities as the temperature increases due to thermal pollution  This option exploits our outside knowledge of air conditioning but from the passage we cannot infer this option. 
  (B)   dissipate the surplus of the release of stored solar energy over absorbed solar energy into space  Interesting and in line with the underlined portion in our pre-thinking 
(C) conserve completely renewable energy sources by requiring that industry replace these resources  out of scope 
(D) avoid further thermal pollution by converting to solar energy as opposed to conventional and nuclear sources  out of scope 
(E) utilize hydroelectric and wood energy to replace nonconventional energy sources such as nuclear energy  out of scope

-6. The tone of the passage is best describe as one of

Pre-thinking

Tone Question

To get the tone of this passage it is fundamental to read carefully the last paragraph and pay attention to an adjective.
  The only practical means of avoiding the problem of thermal pollution appears to be the use of solar energy. (Schemes to “air-condition” the earth do not appear to be feasible before the twenty-second century.) Using the solar energy before it is dissipated to heat does not increase the earth’s energy balance. The cost of solar energy  is extremely favorable now , particularly when compared to the cost of relocating many of our major cities.

As the author mentions the advantages in terms of costs for adopting solar energy, the author is positive.

(A) unmitigated outrage
  (B)   cautious optimism
(C) reckless abandon
(D) smug self-assurance
(E) pronounced alarm  This choice is very tempting because the author mentions many bad consequences if we keep doing what we are doing but such examples are meant to strengthen the bigger idea that solar energy is the way to go and that now it is a favorable time to implement it

7. Which of the following would be the most logical topic for the author to address in a succeeding paragraph?

Pre-thinking

Inference question

The author ended up by talking about costs and how favorable it is now to implement solar energy.

(A) The problems of nuclear safety and waste disposal  out of scope 
(B) A history of the development of solar energy  out of scope 
  (C)   The availability and cost of solar energy technology  In line with pre-thinking 
(D) The practical effects of flooding of coastal cities  out of scope 
(E) The feasibility of geothermal energy  out of scope

It's a great day to be alive!

Heizen · Answer

Solar energy is quickly becoming a source of energy for homes and businesses all over the world. The Bureau of Labour Statistics predicts that jobs for solar energy installers will experience a 63% increase between 2018 and 2028. Due to this industrial growth, there are numerous job opportunities available, including that of a solar energy technician whose work is to construct, install, and maintain solar panel systems.

jigar16496 · Answer

sajjad  question 5 explanation

Sajjad1994 · Answer

Official Explanation

5. It can be inferred that the “air-conditioning” of the earth refers to proposals to

Difficulty Level:   Very Hard

Explanation

This is an inference question. In the  final paragraph  the author makes references to the possibility of  “air-conditioning”  the earth. A word placed in quotation marks indicates that it is being used in a nonstandard way. Ordinarily, we use the word  “air-condition”  to mean to cool, say, a room or an entire building. Obviously, the author is not referring to some gigantic air-conditioning unit mounted, say, on top of the earth. But the general idea of removing heat seems to be what the term means in this context. This is consonant with the passage as well. Thermal pollution is the buildup of energy, and we are showing a positive buildup because fossil fuel and other sources of energy release energy which was only stored. So this, coupled with the sun’s energy which comes in each moment, gives us a positive (though not desirable) balance of energy retention over energy loss. The idea of air-conditioning the earth, though not feasible to the passage, must refer to schemes to get rid of this energy, say, into outer space. This is the idea presented in  (B) .

As for  (A) , redistribution of thermal energy within the earth’s energy system will not solve the problem of accumulated energy, so that cannot be what proponents of  “air conditioning”  have in mind.

(C)  is a good definition of conservation, but not  “air conditioning.”

(D)  is the recommendation given by the author, but that is not a response to this question.

Finally,  (E)  is incorrect for the reason that burning wood is not going to cool the earth.

The correct answer is (B).

Kratosgmat · Answer

Q6 why would a person who is "pronounced alarm" advocate a solution. it wouldnt make sense

Sajjad1994 · Answer

Explained here https://gmatclub.com/forum/at-the-prese ... l#p2199433

At the present time, 98% of the world energy consumption comes from st

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GMAT Reading Comprehension (RC) Questions

At the present time, 98% of the world energy consumption comes from st

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615 to 715 in 15 Days (Ria's Strategies)

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