Scientists have been puzzled by the seeming disparity between models

Can some expert please explain Michael's line of reasoning in Para 1. I am unable to reason how did he reach to his ultimate conclusion that "the models may be flawed"

I understood what his observations were but cannot understand how did he establish the conclusion.

Thanks in advance

Can some expert please explain Michael's line of reasoning in Para 1. I am unable to reason how did he reach to his ultimate conclusion that "the models may be flawed"

I understood what his observations were but cannot understand how did he establish the conclusion.

Thanks in advance

I have a question related question#1 - question stem says

The passage suggests that, in the early 1990s, Michaels would have been most likely to agree with which of the following statements about the disparity mentioned in lines 3-4?

In passage, it was not mentioned when Michaels started doubted his idea. So, what will be the scope of this question?
Should the scope of the answer is before Michaels started doubting his idea, or it can go beyond that?

Also, why option A is incorrect in question#1

A. This disparity is relatively less extreme in the Northern Hemisphere because of sulfate cooling.

I have a question related question#1 - question stem says

The passage suggests that, in the early 1990s, Michaels would have been most likely to agree with which of the following statements about the disparity mentioned in lines 3-4?

In passage, it was not mentioned when Michaels started doubted his idea. So, what will be the scope of this question?
Should the scope of the answer is before Michaels started doubting his idea, or it can go beyond that?

Also, why option A is incorrect in question#1

A. This disparity is relatively less extreme in the Northern Hemisphere because of sulfate cooling.

B. This disparity is only a short-term phenomenon brought about by sulfate cooling.

Question 1

line 7 ~ line 10
In the early 1990's, Pat Micheals sought to explain this disparity, suggesting that
sulfate emissions in industrial areas had a cooling effect, thus temporarily retarding
global warming.

: We should concentrate on a word ' temporarily'

B. This disparity is only a short-term phenomenon brought about by sulfate cooling.

-> temporarily = short-term phenomenon

Question 2

A. It will become a more serious problem in the Southern Hemisphere than in the Northern Hemisphere in spite of the cooling influence of oceans in the south.
-> more serious? : not mentioned
B. It is unlikely to be a serious problem in the future because of the pervasive effect of sulfate cooling.
-> in the future? not mentioned
C. It will proceed at the same general rate in the Northern and Southern Hemispheres once the temporary influence of sulfate cooling comes to an end.
-> will proceed at the same general rate? not mentioned
D. Until the late 1980s, it was moderated in the Northern Hemisphere by the effect of sulfate cooling.
-> Correct
Line 14 ~ Line 17, there is a mention about D
'Yet since 1987, ~ while warming in the north has accelerated'
It means that before 1987, the north has not accelerated.
We can infer 'not accelerated' to 'moderate'
E. Largely because of the cooling influence of oceans, it has had no discernible impact on the Southern Hemisphere.
-> no discernible impact? No. The passage argues that there is a difference between Northern and Southern Hemisphere

Question 3

Line 32 ~ Line 34
'Thus, Santer disputes Michael's claim that model predictions and observed data differ fundamentally.'

Michael's claim : global warming models themselves may be flawed
(model(line 4~6) : global warming based on greenhouse gas emission and actual climatological data)

Santer : disputes Michael's claim

So, A is correct

Question 1

Take a look at the relevant section of the passage:

"In the early 1990s, Pat Michaels sought to explain this disparity, suggesting that sulfate emissions in industrial areas had a cooling effect, thus temporarily retarding global warming. Michaels later came to doubt this idea..."

From this, we know that Michaels made a certain suggestion in the early 1990s. Then we learn that he "later" came to doubt this idea. This means that Michaels doubts occurred after the 1990s. So, to answer question 1, we're looking for an option that corresponds to Michaels' initial suggestion in the early 1990s.

Would the early 1990s Michaels agree with (A) for question 1?
The passage discusses a disparity between global warming models and actual climate data. The actual data showed that the world wasn't warming up as fast as the models predicted.

In the early 1990s, Michaels explained this disparity by saying that sulfate emissions temporarily slow down warming. What did the early-90s Michaels think about cooling in the northern vs southern hemisphere? We have no idea -- the issue with the hemispheres isn't discussed until we learn about his "later" doubts.

This "later" Michaels points out that the south actually had slower warming than the north, which is directly contrary to what (A) tells us. We really can't conclude from this that the early-90s Michaels would agree with the information in (A) -- it could be that he hadn't considered hemispheres at all in the early 1990s.

(A) is out.

Compare that to (B):
The early-90s Michaels believed that sulfate emissions "temporarily" slowed down warming. So, he would agree that the disparity was a short-term issue caused by sulfate emissions.

(A) is the correct answer to question 1.

I hope that helps!

Official Answers and Explanations

1. The passage suggests that, in the early 1990s, Michaels would have been most likely to agree with which of the following statements about the disparity mentioned in the lines 3–4?
A. This disparity is relatively less extreme in the Northern Hemisphere because of sulfate cooling.
B. This disparity is only a short-term phenomenon brought about by sulfate cooling.
C. This disparity is most significant in those parts of the world dominated by oceans.
D. The extent of this disparity is being masked by the temporary effect of sulfate cooling.
E. The disparity confirms that current models of global warming are correct.
Inference
The disparity highlighted in this question is between global warming models and actual climate data—that is, that the models predicted warming that has not occurred. In the early 1990s, according to the passage, Michaels tried to explain this disparity by saying that industrial sulfate emissions had a cooling effect that slowed global warming briefly.
A. The passage does not indicate that Michaels came to distinguish between the Northern and Southern Hemispheres until he began to doubt his early 1990s explanation for the mentioned disparity.
B. Correct. Michaels claimed in the early 1990s that the disparity was temporary, and that it occurred due to the cooling effect of sulfate emissions.
C. Santer’s contention, not Michaels’s, is based on the effect of oceans on global warming.D. In the early 1990s, Michaels used the idea of sulfate cooling to explain the
observed disparity, not to suggest that the disparity itself was larger than observed.
E. In seeking to explain the disparity, Michaels seems to have assumed, in the early 1990s at least, that the models of global warming were correct. But he did not take the disparity as evidence of their correctness.
The correct answer is B.

2. According to the passage, Santer asserts which of the following about global warming?
A. It will become a more serious problem in the Southern Hemisphere than in
the Northern Hemisphere in spite of the cooling influence of oceans in the south.
B. It is unlikely to be a serious problem in the future because of the pervasive effect of sulfate cooling.
C. It will proceed at the same general rate in the Northern and Southern Hemispheres once the temporary influence of sulfate cooling comes to an end.
D. Until the late 1980s, it was moderated in the Northern Hemisphere by the effect of sulfate cooling.
E. Largely because of the cooling influence of oceans, it has had no discernible impact on the Southern Hemisphere.
Supporting idea
The second paragraph of the passage discusses Santer’s take on global warming. He is concerned with the effect of oceans and of sulfate cooling on this process, and he argues that the rate of warming in the Southern and Northern Hemispheres has been differently affected by each of these. In general, oceans slow warming in the south, while sulfate cooling temporarily slowed warming in the north until the late 1980s.
A. According to the passage, Santer has argued that since 1987 the Northern Hemisphere has warmed more significantly than the Southern Hemisphere.
B. Santer maintains that sulfate cooling complicates our attempts to understand global warming. He notes, however, that sulfate cooling peaked in the Northern Hemisphere in the mid-1900s, and that that hemisphere’s warming has increased considerably. So sulfate cooling’s effect is not pervasive and has not mitigated the medium- and long-term problem of global warming.
C. Santer argues that, in the absence of sulfate cooling, global warming would occur more slowly in the Southern Hemisphere due to the greater oceancoverage there.
D. Correct. Santer says that sulfate cooling slowed warming in the Northern Hemisphere, but that in 1987, the influence of sulfate cooling was no longer significant.
E. Santer maintains that global warming happens more slowly in the Southern Hemisphere due to the greater ocean coverage there, not that it has no discernible impact there.
The correct answer is D.

3. The passage suggests that Santer and Michaels would be most likely to DISAGREE over which of the following issues?
A. Whether climatological data invalidates global warming models
B. Whether warming in the Northern Hemisphere has intensified since 1987
C. Whether disparities between global warming models and climatological data can be detected
D. Whether landmasses warm more rapidly than oceans
E. Whether oceans have a significant effect on global climate patterns
Inference
According to the end of the first paragraph, Michaels began to doubt that sulfate cooling had an effect on global warming, and, further, based on the fact that he could not find an answer for why climatological data did not line up with global warming models, he questioned the accuracy of those models. The second paragraph explains that Santer, in contrast, offered a more nuanced explanation for the effect of sulfate cooling, and that based on this explanation, he disputed the claim that climatological data were inconsistent with the models’ predictions.
A. Correct. Based on the passage, Santer and Michaels would clearly disagree about whether climatological data invalidate global warming models: Michaels came to question the models on the basis of those data, while Santer found the model predictions were in fact ultimately consistent with the observed data.
B. Both Santer and Michaels accept the idea that warming in the north has accelerated since 1987.
C. Santer and Michaels both offered reasons for why the seeming disparity between models and data occurred—thus they agreed that such disparities were in fact detected.
D. According to the second paragraph, Santer holds that landmasses warm more rapidly than oceans. But the passage offers no indication that Michaels disagrees with this.E. Santer’s argument is based in large part on the effect of oceans on global climate patterns, but nothing in the passage’s discussion of Michaels’s work indicates that Michaels would disagree that oceans have such an effect.
The correct answer is A.

If M is already questioning the validity of the models based on the data how could he disagree with the issue that climatological data invalidates global warming models

He is questioning the models based on the data derived from Climatological data

Posted from my mobile device

@Bunuel why the answer for 1st question is not D?