Long after the lava has cooled, the effects of a major volcanic erupti

Question

Long after the lava has cooled, the effects of a
major volcanic eruption may linger on. In the
atmosphere a veil of fine dust and sulfuric acid droplets
can spread around the globe and persist for years.
 (5)  Researchers have generally thought that this veil can
block enough sunlight to have a chilling influence on
Earth’s climate. Many blame the cataclysmic eruption
of the Indonesian volcano Tambora in 1815 for the
ensuing “year without a summer” of 1816—when parts
 (10)  of the northeastern United States and southeastern
Canada were hit by snowstorms in June and frosts in
August.

The volcano-climate connection seems plausible,
but, say scientists Clifford Mass and Davit Portman, it
 (15)  is not as strong as previously believed. Mass and
Portman analyzed global temperature data for the years
before and after nine volcanic eruptions, from Krakatau
in 1883 to El Chichón in 1982. In the process they tried
to filter out temperature changes caused by the cyclic
 (20)  weather phenomenon known as the El Niño-Southern
Oscillation, which warms the sea surface in the
equatorial Pacific and thereby warms the atmosphere.
Such warming can mask the cooling brought about by
an eruption, but it can also mimic volcanic cooling if
 (25)  the volcano happens to erupt just as an El Niño
induced warm period is beginning to fade.
Once El Niño effects had been subtracted from the
data, the actual effects of the eruptions came through
more clearly. Contrary to what earlier studies had
 (30)  suggested, Mass and Portman found that minor
eruptions have no discernible effect on temperature.
And major, dust-spitting explosions, such as Krakatau
or El Chichón, cause a smaller drop than expected in
the average temperature in the hemisphere (Northern or
 (35)  Southern) of the eruption—only half a degree
centigrade or less—a correspondingly smaller
drop in the opposite hemisphere.

Other researchers, however, have argued that even
a small temperature drop could result in a significant
 (40)  regional fluctuation in climate if its effects were
amplified by climatic feedback loops. For example, a
small temperature drop in the northeastern U.S. and
southeastern Canada in early spring might delay the
melting of snow, and the unmelted snow would
 (45)  continue to reflect sunlight away from the surface,
amplifying the cooling. The cool air over the region
could, in turn, affect the jet stream. The jet stream
tends to flow at the boundary between cool northern air
and warm southern air, drawing its power from the
 (50)  sharp temperature contrast and the consequent
difference in pressure. An unusual cooling in the region
could cause the stream to wander farther south than
normal, allowing more polar air to come in behind it
and deepen the region’s cold snap. Through such a
 (55)  series of feedbacks a small temperature drop could be
blown up into a year without a summer.   
 1 
 1. Which one of the following most accurately expresses the main idea of the passage?

(A) The effect of volcanic eruptions on regional temperature is greater than it was once thought to be.
(B) The effect of volcanic eruptions on regional temperature is smaller than the effect of volcanic eruptions on global temperature.
(C) The effect of volcanic eruptions on global temperature appears to be greater than was previously supposed.
(D) Volcanic eruptions appear not to have the significant effect on global temperature they were once thought to have but might have a significant effect on regional temperature.
(E) Researchers tended to overestimate the influence of volcanic eruptions on global temperature because they exaggerated the effect of cyclical weather phenomena in making their calculations.

2 
 2. Not taking the effects of El Niño into account when figuring the effect of volcanic eruptions on Earth’s climate is most closely analogous to not taking into account the

(A) weight of a package as a whole when determining the weight of its contents apart from the packing material
(B) monetary value of the coins in a pile when counting the number of coins in the pile
(C) magnification of a lens when determining the shape of an object seen through the lens
(D) number of false crime reports in a city when figuring the average annual number of crimes committed in that city
(E) ages of new immigrants to a country before attributing a change in the average of the country’s population to a change in the number of births

3 
 3. The passage indicates that each of the following can be an effect of the El Niño phenomenon EXCEPT:

(A) making the cooling effect of a volcanic eruption appear to be more pronounced than it actually is
(B) making the cooling effect of a volcanic eruption appear to be less pronounced than it actually is
(C) increasing atmospheric temperature through cyclic warming of equatorial waters
(D) initiating a feedback loop that masks cooling brought about by an eruption
(E) confounding the evidence for a volcano climate connection

4 
 4. Which one of the following most accurately characterizes what the author of the passage means by a “minor” volcanic eruption (line 30)?

(A) an eruption that produces less lava than either Krakatau or El Chichón did
(B) an eruption that has less of an effect on global temperature than either Krakatau or El Chichón did
(C) an eruption whose effect on regional temperature can be masked by conditions in the hemisphere of the eruption
(D) an eruption that introduces a relatively small amount of debris into the atmosphere
(E) an eruption that causes average temperature in the hemisphere of the eruption to drop by less than half a degree centigrade

5 
 5. To which one of the following situations would the concept of a feedback loop, as it is employed in the passage, be most accurately applied?

(A) An increase in the amount of decaying matter in the soil increases the amount of nutrients in the soil, which increases the number of plants, which further increases the amount of decaying matter in the soil.
(B) An increase in the number of wolves in an area decreases the number of deer, which decreases the grazing of shrubs, which increases the amount of food available for other animals, which increases the number of other animals in the area.
(C) An increase in the amount of rain in an area increases the deterioration of the forest floor, which makes it harder for wolves to prey on deer, which increases the number of deer, which gives wolves more opportunities to prey upon deer.
(D) An increase in the amount of sunlight on the ocean increases the ocean temperature, which increases the number of phytoplankton in the ocean, which decreases the ocean temperature by blocking sunlight.
(E) As increase in the number of outdoor electric lights in an area increases the number of insects in the area, which increases the number of bats in the area, which decreases the number of insects in the area, which decreases the number of bats in the area.

6 
 6. The author of the passage would be most likely to agree with which one of the following hypotheses?

(A) Major volcanic eruptions sometimes cause average temperature in the hemisphere of the eruption to drop by more than a degree centigrade.
(B) Major volcanic eruptions can induce the El Niño phenomenon when it otherwise might not occur.
(C) Major volcanic eruptions do not directly cause unusually cold summers.
(D) The climatic effects of minor volcanic eruptions differ from those of major eruptions only in degree.
(E) El Niño has no discernible effect on average hemispheric temperature.

7 
 7. The information in the passage provides the LEAST support for which one of the following claims?

(A) Major volcanic eruptions have a discernible effect on global temperature.
(B) The effect of major volcanic eruptions on global temperature is smaller than was previously thought.
(C) Major volcanic eruptions have no discernible effect on regional temperature.
(D) Minor volcanic eruptions have no discernible effect on temperature in the hemisphere in which they occur.
(E) Minor volcanic eruptions have no discernible effect on temperature in the hemisphere opposite the hemisphere of the eruption.

8 
 8. The primary purpose of the last paragraph of the passage is to

(A) describe how the “year without a summer” differs from other examples of climatic feedback loops
(B) account for the relatively slight hemispheric cooling effect of a major volcanic eruption
(C) explain how regional climatic conditions can be significantly affected by a small drop in temperature
(D) indicate how researchers are sometimes led to overlook the effects of El Niño on regional temperature
(E) suggest a modification to the current model of how feedback loops produce changes in regional temperature

Source:   LSAT Official PrepTest 28   
 Difficulty Level:   700

RC Butler 2021  -  Practice Two RC Questions Everyday.   
Passage # 202 Date: 21-May-2021
 This question is a part of RC Butler 2021 .  Click here for Details

Saasingh · Answer

Total time : 17 minutes 13 seconds.

6/8 correct.

Got Q2 and Q3 wrong.

Q3 was a haste/silly mistake for me but I do not understand Q2 at all.

Any explanation of Q2. 
 
I chose A  because like El nino, we need to subtract the element from our calculations which distorts the final value. As in, we need to not consider that element, which is extra and which hampers our correct result.
This is analogous to option A. We do not consider whole package weight, because our final result should include only contents of package and not total package material.

I fail to see how option E is correct.

Any help ?

bond001 · Answer

QUESTION 2 
CONFUSED BETWEEN D AND E

Sajjad1994 · Answer

(D)  goes wrong in that its goal is not to figure out the effect of some phenomenon (as in  (E)  and in the stimulus), but rather to make a straightforward computation.  (D)  would have been closer if it had evaluated whether something affects the crime rate. That is why D is wrong and E is correct.

CEdward · Answer

I didn't get 2 either. Had the exact same reasoning. The El Nino distorts our ability to see the actual effects of the volcano on temperature so you have to strip it before doing the analysis.

But, these LSAT passages are absolutely brutal. I got 3 wrong and took me 17 minutes. Are the GMAT questions this difficult?

I have found so far that GMAT RC questions are far easier (from the practice ones available)

RiteshGadave · Answer

Sajjad1994  Sir ....Can you please explain question no. 3 and 4??? Nothing about debris is mentioned in the paragraph...so how do we arrive at option D for question 4 ??? I also didn't get why Option B is wrong for question 3

Sajjad1994 · Answer

Explanation

3. The passage indicates that each of the following can be an effect of the El Niño phenomenon EXCEPT:

Difficulty Level:   700

Explanation

The important thing here is that you restrict your analysis to  Paragraph 2  and the early part of  Paragraph 3 , the only places in which El Niño comes into play. From  lines 18-29  we basically get four facts about El Niño, and not coincidentally, those four facts have been turned into the four wrong choices.

Lines 18-22  say that El Niño warms the surface of the Pacific and hence— choice (C) — "warms the atmosphere."   Paragraph 2  continues by noting that an El Niño can  “mask the cooling brought about by”  a volcano erupting —that’s  (B) ; and then it says that, conversely, an El Niño can  “mimic...cooling,”  i.e. can make things seem cooler than they really are. That’s  (A) .

As a result, says  Paragraph 3 , by eliminating El Niño from the calculations you can get a truer picture, one that gets to the heart of the volcano-climate connection. That’s  (E) .

(D)  is perhaps hard to fix upon because its use of the phrase  “masks cooling”  conjures up a point  (line 23)  that is in the midst of the El Niño discussion. But the whole concept of  “feedback loops”  doesn’t arise until two paragraph’s later!  Paragraph 4  is about a whole different kind of relationship between volcanoes and climate, and by then we’ve left all consideration of El Niño far behind. If you chose  (D)  as an effect of El Niño you were working too hard to see a  “feedback loop”  at work in  lines 18-29 . The author doesn’t use the phrase in that specific context, so why should we?

Answer: D

4. Which one of the following most accurately characterizes what the author of the passage means by a “minor” volcanic eruption (line 30)?

Difficulty Level:   650

Explanation

“Minor eruptions”  are polished off briskly, both by Mass & Portman and by the author. When you discount the effects of El Niño, says  lines 30-32, “minor eruptions have no discernible effect on temperature. And major, dust-spitting explosions,...” —that emphasis is ours, to highlight that the minor eruptions in question are used by the author to contrast with the big dust-spitters.  (D)  is a discreet paraphrase of  “minor dust-spitter.”

(A)  The issue ever since  line 3  has been dust, not lava. Remember sentence 1? The entire passage is concerned with what happens  “long after the lava has cooled.”

(B)  is a distortion that takes two issues, global temperature and the names of two major volcanic events, and merges them together unacceptably. To the author, an eruption is  “minor”  or  “major”  sheerly because of its dust quotient, and not because of its effect on temperature.  (B) ’s focus on Krakatau and El Chichón is too narrow and misses the point.

(C), (E)  Minor eruptions  “have no discernible effect on temperature,”  so there’s nothing to mask,  (C) , and no drop in average hemispheric temperature is caused,  (E).

Answer: D

Explanation Credit: Kaplan LSAT

RiteshGadave · Answer

Thank you so much sir...I get it now.

dharam44 · Answer

Please elaborate the question no. 2.

Sajjad1994 · Answer

Explanation

2. Not taking the effects of El Niño into account when figuring the effect of volcanic eruptions on Earth’s climate is most closely analogous to not taking into account the

Difficulty Level:   750

Explanation

El Niño, you’ll recall, is a major weather phenomenon whose warming effect can either mask a volcanic eruption’s cooling, or mimic it  (lines 23-26) . Once El Niño’s effect is subtracted, the effect of a volcanic eruption on global climate is seen to be minimal. Not having subtracted El Niño, then—and that’s what the question asks us to consider—leads to a logical distortion. Doing so would be tantamount to ignoring a huge alternative explanation for certain climatic conditions, one that renders dubious indeed any conclusions drawn about volcanoes’ influence.

So an analogous situation will involve the failure to subtract some key factor that ought at least to be considered in drawing one’s conclusion. And this is what  (E)  presents. Before you decide that the change in a population’s average age must be due to a higher birth rate, better check out other plausible explanations—such as the one  (E)  suggests, the ages of new immigrants to the country. Maybe so many of them are old or young that that is what caused the higher average age; maybe the birth rate is really stable (just as volcanic eruptions are really negligible in terms of climatic change). Ignoring those immigrants would be like ignoring El Niño—turning a blind eye to an alternative explanation.

(A)  To not take into account  “the weight of the package as a whole”  when trying to determine the contents’ weight would be impossible—unless you were to remove the contents and weigh them separately, in which case the weight of the overall package would be of no interest to you. Either way,  (A)  isn’t a case of misleading data.

(B)  If your goal was to count the number of coins in a pile, it would be totally appropriate to not take into account the coins’ monetary value.

(C)  Without field-specific, technical knowledge uncalled-for by the LSAT, it is difficult to imagine how not taking into account lens magnification would affect the determination of an object’s shape. The shape is what it is; the magnification, inferably, might affect its size but not its shape.

(D)  goes wrong in that its goal is not to figure out the effect of some phenomenon (as in  (E)  and in the stimulus), but rather to make a straightforward computation.  (D)  would have been closer if it had evaluated whether something affects the crime rate.

Answer: E

Explanation Credit: Kaplan LSAT

RB95 · Answer

I got Qns 2 correct. Even I was stuck between option D and E.

2. Not taking the effects of El Niño into account when figuring the effect of volcanic eruptions on Earth’s climate is most closely analogous to not taking into account the

(D) number of false crime reports in a city when figuring the average annual number of crimes committed in that city
(E) ages of new immigrants to a country before attributing a change in the average of the country’s population to a change in the number of birth

My reasoining for chosing option E are as below.

In determining the effects on temperature, the effects of EL Nino were not taking into consideration and all the temperature
changes were attributed to volcanic eruptions, similarly all the population change was attributed to new births without taking into consideration the age of immigrant children.

eliminating option D is a bit tricky. Option E, as does the passage, introduces a completely NEW phenomenon to refute 
the calculations whereas D just infers that there may have been some false statistics while calculating.
So if D were to be the right option, the passage might have suggested some error in calculating temperature variation and
not a completely new reason (EL Nino) to overshadow the effects of volcanic eruptions.

Vishalcv · Answer

Why I didn't choose E is because El Nino played a huge role in the analysis of the effect of volcanic eruptions on climate, whereas the new immigrant number might well be minimal when compared to the entire population of a country, so it may not have that much of an effect. Again, I say "may not" , because we simply do not have enough data to comment. I feel E is a very incomplete option

AdiBir · Answer

You were on the right path but if you read option A carefully, it will only skew the results in one direction, i.e adding package weight will only give increased weight whereas El-nino can either amplify the cooling impact or dampen it. 
Option E corrects this gap. The immigrant population can either increase or decrease avg. age depending on the age of the immigrants, hence it is more analogous.

Hope this helps!!

elPatron434 · Answer

Hi  GMATNinja   GMATNinjaTwo   VeritasKarishma  
Can you please explain why choice A is incorrect for Q3?
The option says making the cooling effect of a volcanic eruption appear to be more pronounced than it actually is

In the passage it is given that

Such warming can mask the cooling brought about by
an eruption, but it can also mimic volcanic cooling if
(25) the volcano happens to erupt just as an El Niño
induced warm period is beginning to fade

From these lines I understand that elNino can make things as cool as a volcanic eruption under some conditions, at best. I'm not sure how it can be implied that the cooling effect by volcanic eruptions can be amplified by el Nino.

Could you please help me with this?

yahya729 · Answer

Question 1 - main point.

Correct answer D. The author hasn't tried to argue whether the effects of volcanic eruptions are greater or not, but just presented sides. He also hasn't tried to compare variances in global vs regional, but just used those as examples to say that the effects could be large or small, so A, B and C are out. Finally E is completely out of scope as the main point isn't to criticize researchers.

Question 2 - impact of El-nino's analogy.

El-nino basically has an effect due to which the volcanic effect isn't as large. so to get an realistic analysis of the volcanic effect, we need to filter out Elnino's effect.

From the choices given, only E does something similar. you can't say that a countries population (in our case the temperate) has increased (decreased for us) because of more births. since immigrants (El-nino) have increased the population as well, the effects of more births (volcanic eruptions for us) is lesser than expected

Question 3 - effect of Elnino except.

Again, Elnino basically masks the volcanic effect. A,B and E say exactly that. C - warming of equatorial waters is mentioned. D is correct due to also process of elimination, but also because feedback loops are mentions in paragraph three which isn't related to Elnino

Question 4 - what are minor erupsions

reading on from line 30 "And major, dust-spitting explosions, such as Krakatau, or El Chichón"... thus a minor eruption is not a major dust-spitting explosion hence D

Question 5 - what is a feedback loop.

Tough question, moreso also because the answer choices are long. But what exactly is a feedback loop to start with? Something small which later on becomes something bigger due to domino effects in the middle. So all you're looking for is a small effect which leads to same effect later. only A answers that. decaying matter in soil leads to more decaying matter in soil. Wolves leading to animals is close, but A is the better option - the others aren't talking about the same effect

Question 6 - what hypothesis would the author not agree with

So from reading the passage we know that the author present 2 sorts of point of views and nothing extreme. for A, half a degree is mentioned, so this is out. B major eruptions don't induce elnino, they happen serpately. C is correct because the last paragraph is all about the feedback loop where things happens indirectly. D again mentions one degree which half a degree in the passage, and the difference is 0-0.5, and E is wrong also because passage 2 is all about how Elnino has an impact

Question 7 - least evidence for which of the following claims.

Okay, so the hardest question of the lot, moreso because you may also not know what discernable means. hence how do you eliminate A? is discernable big impact or a small impact? if its big, A is wrong, if its small, this could be right. so lets ignore this for now. 
B - major eruptions have a smaller impact. The 2nd passage is all about this. 
Aha - so what does B actually do? it actually answer A. Why would you have 2 options choices saying major eruptions have a smaller impact? so A must mean the volcanic eruptions have a big impact. so that was mentioned in passage 1, hence A is out also. 
And now you've figured out what discernable kind of means. 
D - mentioned in para 2.

so now you're down to C and E. For E, at end of passage 2, the author mentions the major eruptions have an impact in the opposite hemisphire, but it doesn't talk about minor eruptions, and for C, the passage talking multiple times of volcanic eruptions. so you may have to guess - the trick is that passage 2 is about global temps and passage 3 is about regional temps. choice C is about major eruptions not having a big impact in regional temps, but the whole passage is about them having, so it'd kind of opposite of what the author is saying.

Anyone have any idea how to eliminate E properly here?

Question 8 - purpose of last para

the author presents the last para really to talk about the effect a volcanic eruption can have. which goes again para 2. he talks about the feedback loop, which is a small change making an impact. C directly talks about this. B, D and E are completely out since the author never mentions them. you may be confused between A and C, because the author mentions a year without summer, but that is the opposite. A feedback loop results in year without summer. Hence C

I totally deserve a kudos for doing this during office time on a Friday

Deadpool3 · Answer

Hi  elPatron434

You are correct in your understanding that the ElNino makes things as cool as a volcanic eruption. But that does not mean that at the time temperature was as down as it could be. Suppose Volcanic eruption could take temp. to -20 degrees C. and ElNino can also mimic this. But What if ElNino mimicked this temperature but the Volcanic eruption did not take the temp to this low. Now it will make you will understand that Elnino made it more pronounced than it actually is/was.

(A) making the cooling effect of a volcanic eruption appear to be more pronounced than it actually is

P.S: I also got this question wrong for the same reason, but after that when I analyzed it made sense.

starbuzz · Answer

hi  Sajjad1994

can you please explain question 7

Sajjad1994 · Answer

Explanation

7. The information in the passage provides the LEAST support for which one of the following claims?

Difficulty Level:   700

Explanation

This is an Except question and looking for the odd man out. Four of the choices are supported by the text; one is not.

(A)  directly echoes  lines 32-37 . The effect of major eruptions on global temperature is discernible—if minor.

(B)  When you compare the conclusion in  lines 32-37  with what  “researchers have generally thought”  as described back in  lines 5-12 , you have to acknowledge that volcanoes aren’t given the same amount of credit for the temperature change that they used to be.

(C)  directly contradicts  (A)  which—as we’ve just seen—itself directly echoes the passage in  Paragraph 3.  So  (C)  is what we want here. The big, big eruptions do have an effect, albeit less than was previously supposed.

(D), (E)  Since  “minor eruptions have no discernible effect on temperature” (lines 30-31) , the hemisphere is irrelevant, so  (D)  and  (E)  follow from Mass and Portman’s findings.

Answer: C

desertEagle · Answer

Kindly explain the following query related to option D and E

(D) number of false crime reports in a city when figuring the average annual number of crimes committed in that city - If we dont take into account the number of false crime reports, it will inflate the average annual number of crimes because false crime reports will also be added to the total. This is akin to how if effects of el nino are not subtracted may inflate our estimate of increase in global temperature
(E) ages of new immigrants to a country before attributing a change in the average of the country’s population to a change in the number of births - here ages of new immigrants is being compared to change in population. You cant add age to population or number of births. use of "thoese of" or "that of" is missing suggesting that age is being added to number of births which is being used to calculate country's population.

Kindly explain

vyom001 · Answer

Can you please post the answer to Q6. I chose A and want to see the OA.

Long after the lava has cooled, the effects of a major volcanic erupti

Prep Toolkit

Top 5 GMAT Debrief Videos

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

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards

GMAT Reading Comprehension (RC) Questions

Long after the lava has cooled, the effects of a major volcanic erupti

Prep Toolkit

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

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards