V37-17

Question

Some city planners argue against the construction of new skyscrapers in urban areas, claiming that taller buildings increase the "urban heat island" effect, making cities warmer. They suggest that this increase in temperature exacerbates pollution and impacts public health. In response, advocates for skyscraper construction argue that, with modern energy-efficient designs, skyscrapers can actually reduce overall urban temperatures by centralizing populations and reducing urban sprawl.
 
Which of the following, if true, most seriously weakens the skyscraper advocates' argument?

A. Urban sprawl has been shown to contribute significantly to increased vehicle emissions, which are a major source of urban pollution.
B. Studies have demonstrated that the energy-efficient designs of new skyscrapers often fail to perform as well as projected, resulting in higher energy consumption.
C. In cities with a high concentration of skyscrapers, a significant decrease in green spaces has been observed, contributing to higher urban temperatures.
D. The construction of skyscrapers frequently disrupts existing communities and leads to increased housing costs in urban areas.
E. Energy-efficient skyscrapers require a substantial initial investment, making them less economically feasible than traditional building designs.

Bunuel · Answer

Official Solution:

Some city planners argue against the construction of new skyscrapers in urban areas, claiming that taller buildings increase the "urban heat island" effect, making cities warmer. They suggest that this increase in temperature exacerbates pollution and impacts public health. In response, advocates for skyscraper construction argue that, with modern energy-efficient designs, skyscrapers can actually reduce overall urban temperatures by centralizing populations and reducing urban sprawl.
 
Which of the following, if true, most seriously weakens the skyscraper advocates' argument?

A. Urban sprawl has been shown to contribute significantly to increased vehicle emissions, which are a major source of urban pollution.
B. Studies have demonstrated that the energy-efficient designs of new skyscrapers often fail to perform as well as projected, resulting in higher energy consumption.
C. In cities with a high concentration of skyscrapers, a significant decrease in green spaces has been observed, contributing to higher urban temperatures.
D. The construction of skyscrapers frequently disrupts existing communities and leads to increased housing costs in urban areas.
E. Energy-efficient skyscrapers require a substantial initial investment, making them less economically feasible than traditional building designs.

A. Urban sprawl has been shown to contribute significantly to increased vehicle emissions, which are a major source of urban pollution.
 
 This answer choice actually strengthens the argument since their argument is that the Skyscrapers reduce urban sprawl. Eliminate.
 
B. Studies have demonstrated that the energy-efficient designs of new skyscrapers often fail to perform as well as projected, resulting in higher energy consumption.
 
Incorrect - outside of the scope. This answer choice points to a flaw in the energy efficiency of skyscrapers but it is not relevant to the argument. It is not clear if it is slightly or significantly higher energy consumption and we are not even talking about energy consumption. This choices does not even address the urban heat island effect. 
 
C. In cities with a high concentration of skyscrapers, a significant decrease in green spaces has been observed, contributing to higher urban temperatures.
 
 This choice weakens the skyscraper advocates' argument that modern, energy-efficient skyscrapers can reduce overall urban temperatures. It presents evidence that the construction of skyscrapers leads to a reduction in green spaces, which is a factor known to contribute to higher urban temperatures. This would challenge the claim that skyscrapers would help reduce urban heat.
 
D. The construction of skyscrapers frequently disrupts existing communities and leads to increased housing costs in urban areas.
 
 Incorrect - Irrelevant. Agree, this may be true, but what is the relevance of this choice to the heat island and making cities warmer? We see no connection. This is a true statement, but irrelevant to the argument. 
 
E. Energy-efficient skyscrapers require a substantial initial investment, making them less economically feasible than traditional building designs.
 
 Incorrect - Irrelevant. OK, so the building are more expensive to build if they are energy-efficient but that cost and ecomomics are not a part of the argument. We are only concerned with heat, not ROI or costs.

Answer: C

haesung0204 · Answer

Why can't D be an answer?

D. The construction of skyscrapers frequently disrupts existing communities and leads to increased housing costs in urban areas.

In my breakdown, if D is true, skyscrapers may decentralize population from disrupted existing communities and increased housing costs and increase the overall urban temperature.

parveshrangan · Answer

I also thought that D is an answer

bb · Answer

Thank you for the question. I have improved the explanation to be more readable and better formatted.

Our argument is focused on the argument that   taller buildings increase the "urban heat island" effect, making cities warmer   vs.   skyscrapers can actually reduce overall urban temperatures by centralizing populations and reducing urban sprawl.

Our job is to weaken advocates by evaluating additional evidence presented:

Now, answer choice  D) The construction of skyscrapers frequently disrupts existing communities and leads to increased housing costs in urban areas.

How does disrupting communities or increased housing costs adds to warmth?

bb · Answer

I am sorry for a late reply, I am not following this fully. 
 I do not see how D impacts the rising temperatures.

P.S. We are told that skyscrapers impact communities by centralizing populations and reducing urban sprawl, which is opposite of what you are suggesting.

crystalgirl123 · Answer

I did not quite understand the solution. I answered B. Given the advocate argues that modern energy-efficient designs would centralize populations and reduce urban sprawl, it would be detrimental to their argument if there were studies that showed those very same modern designs actually do not work. If they result in higher energy consumption (ie the pollution mentioned in the first sentence), then there would be more heat.

At its core I don't believe I understood what urban heat island truly meant from the passage. A Google search after revealed that this phenomenon results from pavement (more heat-absorbing) replacing natural land covering. If I had known that context, then I would have gravitated to an answer more about green spaces. I had thought that urban heat was caused by density of human activities, as use of energy generates heat, which also informed why I chose B since there was mention of heat consumption.

Mourya91 · Answer

I don’t quite agree with the solution. Option C is an example of correlation does not equal causation. There is a correlation between cities with high concentration of skyscrapers and a decrease in green space, it does not specify that skyscrapers are the reason for reduced green space.

bb · Answer

Hi. Thank you for the feedback.

Remember, a weaken answer need not deliver courtroom-level proof; it just has to tip the scales of plausibility against the conclusion. Option C shows that in the real world, clusters of skyscrapers correlate with hotter, not cooler, urban environments, exactly the opposite of what the advocates predict. That correlation is enough to erode confidence in their claim, which is why C weakens the argument more than any other choice, even if it doesn’t prove causation outright.

bb · Answer

Hi. I am sorry for missing your question.

I see why B looked tempting, but here’s why C hurts the argument more:

What the advocates are claiming:

1. Design premise: modern, energy-efficient skyscrapers themselves won’t add much heat.

2. Sprawl premise: packing people upward reduces sprawl, so the net effect will be cooler cities.

To beat their argument you can attack either premise, or, better, show a direct counter-effect on temperature.

B says some “energy-efficient” designs under-perform and use more energy.

That chips away at premise 1, but only indirectly threatens the conclusion: more energy use may create more waste heat or pollution—but GMAT CR doesn’t let us assume that extra kilowatt-hours automatically translate into a hotter city.

Even if premise 1 collapses, the advocates could still argue that the sprawl benefit (premise 2) outweighs any design shortfall. In other words, B raises doubt, but it doesn’t give us a clear reason to believe the overall temperature will rise.

C says: Where skyscraper density is high, green space is lost which leads to higher temperatures result.

That evidence hits both premises at once: it shows the real-world outcome is hotter, not cooler, so the design plus anti-sprawl combo plainly isn’t working.

Because it goes straight to the advocates’ promised net effect, it does more damage than B’s partial premise poke.

Sushi_545 · Answer

Hi  bb ,

No I dont agree with your explanation we are told "  skyscrapers can actually reduce overall urban temperatures by centralizing populations and reducing urban sprawl."--> its given in the passage that urban temp can be reduced by centrlizing pouplation and reducing urban sprawl. So D is the right choice
  
isnt the cause "centralizing populations and reducing urban sprawl." produce effect "reduce overall urban temperatures" hence to weaken it we need to weaken the cause which is done by D specifically?

bb · Answer

Hi. Thank you. Can you tell me ab it more how you see D working to weaken the argument? How does it increase/reduce the temperatures?

D. The construction of skyscrapers frequently disrupts existing communities and leads to increased housing costs in urban areas.

Choice D) introduces two social side-effects:

Existing community disruption  
 Higher housing prices

Neither statement denies that skyscrapers centralize people, shows that sprawl fails to shrink, or shows that temperatures fail to drop (or even rise).

juacob · Answer

I don’t quite agree with the solution. Hello, can you help me?

i chose B because i thought it may an example of correlation =/= causation. Sure, where there ́s more skycrapers there may be less green areas because a lot of them were built, but that does not mean it is completely because of the skycrapers or that it will happen to our city, because we don ́t know the number of skycrapers they will build or if the less green areas are actually because of the skycrapers.

Thanks in advance!

bb · Answer

Hi. You are correct about some things. Though in the weaken questions, you don’t have to destroy the argument or prove it wrong, you just need enough to cast a doubt, Plant a seed of doubt.

And while C) may not be the world‘s strongest weakener, it does it’s job, whereas, B) is talking about energy efficiency which is not the same as what the question and arguments are talking about, so I think given the choice between a Soft weakener and B), I would choose C)

kartickdey · Answer

bb  I did not choose C because of the phrase"High concentration"
when something in a high concentration it might have some adverse effect but it does not mean that that stuff is not useful. There are multiple stuff which work up to a optimal level and have negative effect when used excessively.

bhanu29 · Answer

In weakening plan-based questions, we just need to find a reason to doubt the plan. That doesn’t mean the plan won’t work; even if it makes a small dent in the argument, it is the correct answer.

In this question, we see that a high concentration of skyscrapers leads to reduced green spaces, which contributes to higher urban temperatures.

This gives us a reason to doubt the argument. If skyscrapers create the problem they are meant to solve, they may not solve the problem, or at least may fail to offset the damage they caused.

Hope it helps!!

JunterHones · Answer

I don’t quite agree with the solution. I believe that there is an argument to be made for option D. The skyscraper advocates' argument is that skyscrapers reduce overall urban temp by centralizing populations. If there is an increase in housing costs in urban areas, this would not centralize populations and would not reduce urban sprawl, weakening their argument.

bhanu29 · Answer

This is an unwarranted assumption. 
An increase in housing costs does not necessarily mean populations will not centralize, there are other factors to consider. For example, housing costs in NYC are very high, yet most apartments maintain 100% occupancy. Therefore, we cannot conclude that higher costs would weaken the argument.

In contrast,  Option C  presents a counter-factor that directly impacts the problem skyscrapers were intended to solve. By showing that they lead to a decrease in green space, it directly weakens the advocates' claim regarding temperature reduction

Hope it helps!!

V37-17

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