Since the 1850s researchers have tried to show that variations in seas

Question

Since the 1850s researchers have tried to show that variations in seasonal weather are connected in some way with sunspots, the outward sign of an increase in the Sun's activity. However, scientists lacked evidence supporting such a link until the mid-1980s, when van Loon and Labitzke compiled statistical evidence suggesting that a link exists and that it involves winds in the upper atmosphere above the equator which reverse their direction, from east to west or west to east, every twelve to fifteen months. This phenomenon is called the quasi-biennial oscillation (QBO), and although meteorologists have known about the QBO since the 1950s, until the 1980s no one recognized a subtle but statistically significant link between the QBO and certain patterns of weather. When the west to east direction of winds in the upper atmosphere coincides with periods of high solar activity that occur approximately every eleven years, winters in the eastern and central United States are very cold.

On this basis, some meteorologists predicted that the winter of 1988-1989 in the United States would be severe. However, the winter was a mild one overall, and the meteorologists' attempt to make the connection between the Sun and weather on the Earth appeared unsuccessful, until Barnston and Livezey proposed a hypothesis explaining why the prediction had failed. They argued that the prediction had not taken into account another important element in the climate: the more or less regular pattern of fluctuations in the temperature of the surface waters of the tropical Pacific Ocean.

Barnston and Livezey noted that when the water temperature is abnormally high-the phenomenon called EI Niño- the chances of cold winter weather over North America increase. The opposite situation, when surface temperatures are well below normal-La Nina-is far less common. In fact, until late 1988 no one had seen the combination of La Nina, westerly winds in the upper atmosphere, and high solar activity. Thus, according to Barnston and Livezey, La Nina canceled out the effect of the other two climatic factors and caused the mild winter of 1988-1989. Although this hypothesis is plausible, much research remains to be done before meteorologists can establish and explain the effects of increased solar activity on seasonal weather changes.    1 
 D 
 1: The author of the passage would most likely agree with which of the following statements about the link between increased solar activity and certain seasonal weather changes on the Earth?

A. Because the evidence supporting such a link is questionable, future research in this particular area does not look promising.
B. Because it is unlikely that such a link can be definitely established, scientists should concentrate their efforts on investigating the role La Nina and other climatic factors play in influencing global weather patterns.
C. Although some circumstantial evidence suggests that such a link exists,it is unlikely that future research will be able to confirm the existence of this link
D. There is evidence supporting the existence of such a link, but without further scientific investigation that evidence cannot be considered proof that such a link exists.
E. Since the evidence clearly supports the existence of such a link, further research should focus on determining the implications of this link for the accurate prediction of changes in global weather patterns

2 
 E 
 2: The passage provides information to support which of the following statements about La Nina?

A. Its occurrence is more likely to coincide with periods of high solar activity rather than low solar activity
B. It is more likely to occur when the winds in the upper atmosphere above the equator are blowing from the west rather than from the east
C. It occurs more frequently than do shifts in the winds in the upper atmosphere above the equator
D. It occurs less frequently than does increased solar activity
E. It occurs less frequently than does EI Niño

3 
 B 
 3: Which of the following most accurately describes the organization of the passage?

A. A hypothesis is presented, a theory is constructed on the basis of the hypothesis, and then further research to expand the scope of the theory is proposed
B. A hypothesis is presented, an example that contradicts it is described, and then a hypothesis accounting for the apparent contradiction is proposed.
C. Two opposing hypotheses are stated, and evidence confirming one of the hypotheses is considered
D. A phenomenon is described, a prediction about that phenomenon is made, and evidence confirming the accuracy of the prediction is presented.
E. A prediction about a phenomenon is detailed and evaluated, and evidence demonstrating the inaccuracy of the prediction is presented

4 
 E 
 4. The passage provides information to support which of the following statements about the occurrence of very cold winters in the eastern and central United States?

A. Such winters are most likely to occur if the winds in the upper atmosphere over the equator blow from the east rather than from the west.
B. Such winters are most likely to occur if increased activity of the Sun coincides with the appearance of La Nina
C. Such winters are less likely to occur if increased activity of the Sun coincides with the appearance of EI Niño
D. Such winters are less likely to occur if there is an increase in the number of sunspots on the surface of the Sun
E. Such winters are less likely to occur if there is a drop in the temperature of the surface waters of the tropical Pacific Ocean

RC Butler 2021  -  Practice Two RC Questions Everyday.   
Passage # 46 Date: 02-Feb-2021
 This question is a part of RC Butler 2021 .  Click here for Details

Unknown_ · Accepted Answer

1: The author of the passage would most likely agree with which of the following statements about the link between increased solar activity and certain seasonal weather changes on the Earth? 
A. Because the evidence supporting such a link is questionable, future research in this particular area  does not look promising . -too pessimistic
B. Because it is  unlikely that such a link can be definitely established , scientists should concentrate their efforts on investigating the role La Nina and other climatic factors play in influencing global weather patterns. -too pessimistic
C. Although some circumstantial evidence suggests that such a link exists,it is  unlikely that future research will be able to confirm  the existence of this link -too pessimistic
D. There is evidence supporting the existence of such a link, but without further scientific investigation that evidence cannot be considered proof that such a link exists. - Correct , Subtle and inline with the last para
E. Since the  evidence clearly supports  the existence of such a link, further research should focus on determining the implications of this link for the accurate prediction of changes in global weather patterns -too optimistic, nothing is "clearly" supported

2: The passage provides information to support which of the following statements about La Nina? 
A. Its occurrence is more likely to coincide with periods of high solar activity rather than low solar activity
B. It is more likely to occur when the winds in the upper atmosphere above the equator are blowing from the west rather than from the east
C. It occurs more frequently than do shifts in the winds in the upper atmosphere above the equator
D. It occurs less frequently than does increased solar activity
E. It occurs less frequently than does EI Niño  Correct.  From the lines "The opposite situation, when surface temperatures are well below normal- La Nina-is far less common. "

3: Which of the following most accurately describes the organization of the passage? 
A. A hypothesis is presented, a theory is constructed on the basis of the hypothesis, and then further research to  expand the scope  of the theory is proposed -no talk about "expansion of scope"
B. A hypothesis is presented, an example that contradicts it is described, and then a hypothesis accounting for the apparent contradiction is proposed. -  Correct 
C.  Two opposing hypotheses  are stated, and evidence confirming one of the hypotheses is considered
D. A phenomenon is described, a prediction about that phenomenon is made, and  evidence confirming the accuracy  of the prediction is presented. - evidence did not confirm the hypothesis
E. A prediction about a phenomenon is detailed and evaluated, and evidence demonstrating the inaccuracy of the prediction is presented -partial, B is more elaborate - by stating that the reason for contradiction is proposed

4. The passage provides information to support which of the following statements about the occurrence of very cold winters in the eastern and central United States? 
A. Such winters are most likely to occur if the winds in the upper atmosphere over the equator blow from the east rather than from the west.
B. Such winters are most likely to occur if increased activity of the Sun coincides with the appearance of La Nina
C. Such winters are less likely to occur if increased activity of the Sun coincides with the appearance of EI Niño
D. Such winters are less likely to occur if there is an increase in the number of sunspots on the surface of the Sun
E. Such winters are less likely to occur if there is a drop in the temperature of the surface waters of the tropical Pacific Ocean -  Correct . From "Barnston and Livezey noted that when the  water temperature is abnormally high -the phenomenon called EI Niño- the  chances of cold winter weather over North America increase ."

mSKR · Answer

Summary of passage: 
Find relationship between solar activity and weather conditions 
Theory1: established in 1980s, predicted for 1988 but results didn’t match expectation. That gave rise to consideration of other factor but yet proof has not yet established.
Future research is recommended to understand the effects .

A, B and C goes in opposite direction of the key message mentioned in passage. E goes a little further claiming that evidence has already been established and now they need to look for prociese results. D establishes at right key message that results support but further research is needed.

D matches the correct message given in passage,

1st hypothesis: west to east direction of winds in the upper atmosphere (X) + periods of high solar activity that occur approximately every eleven years (Y) == > MILD WINTER
2nd hypothesis : (X) + (Y) + the water temperature is abnormally high (( EI Niño=Z) ) == > COLD WINTER

A, B , C and D options are given to confuse. As per equation, La Nina and X or Y are independent entities. 
Varying X or Y or Z would vary winters.

A: Reject: When Y decreases chances of cold winter decreases but it has no effect on LA nina. La nina is independent entity. 
B: Reject: La Nina means water temperature. X and Z are independent entities 
C: Reject : No direction given ( ( Z- west to east ) and Z’ east to west) independent of El Nina 
D: Reject: Y and La nina are independent entities 
E: Comparison between EI Niño vs LA nina
The opposite situation, when surface temperatures are well below normal-La Nina-is far less common
El nino occurs less frequently than La Nina

Correct E

A and E misses point about 2nd consideration
C. both hyphothesis are not in parallel but one after another i.e. 2nd hyphothesis consoders 1st theory to bring missing consideaiton factor

Between B and D:

Thus, according to Barnston and Livezey, La Nina canceled out the effect of the other two climatic factors and caused the mild winter of 1988-1989. Although this hypothesis is plausible,

Above statement distinguishes between B and D, We can see that 2nd is hyphotesis but no evidence was presented.  Hence B wins over D

Why very cold winters did happen?

1st hypothesis: west to east direction of winds in the upper atmosphere (X) + periods of high solar activity that occur approximately every eleven years (Y) == > MILD WINTER
2nd hypothesis : (X) + (Y) + the water temperature is abnormally high (( EI Niño=Z) ) == > COLD WINTER

A: Reject : From above equation if X becomes –X then cold winter chances are reduced. 
-x means direction of wind from east to west
B: Reject: 
when surface temperatures are well below normal-La Nina-is far less common
you can consider
given Z’< Z 
(X) + (Y) + (Z’ ) -- > so chances of cold winter reduces

C. Reject If Y increase then Cold winter increase 
D. Reject: same as C: If Y increases ( sun spots increases means sun activity increases ) then chances should increase, 
E: opposite of B , 
 When Z decreases overall cold winter decreases , hence less likely

rocky620 · Answer

bm2201

Although I got the last question correct by POE, I could not understand the shift from North America to Central & Eastern US (I know that US is a subset of North America).

When the west to east direction of winds in the upper atmosphere coincides with periods of high solar activity that occur approximately every eleven years, winters in the  eastern and central United States  are very cold.

Barnston and Livezey noted that when the water temperature is abnormally high-the phenomenon called EI Niño- the chances of cold winter weather over  North America increase .

toni08 · Answer

how do we know that in question 2, La Nina is less common than el nino?

Haardy7007 · Answer

Last passage says “ The opposite situation, when surface temperatures are well below normal-La Nina-is far less common”

toni08 · Answer

Okay, but how do we know that here both the La Nina and El Nino are compared? It just says the opposite situation but can we really generalize this?

KittyDoodles · Answer

Hi Experts,

Please advise for QS 3, why Option A is incorrect.

Thanks
Kitty

Sajjad1994 · Answer

Option A  is incorrect because it does not accurately describe the organization of the passage. Let's break down the passage to see why:

-The passage begins by discussing the historical attempts to link variations in seasonal weather with sunspots.
-It then introduces the concept of the quasi-biennial oscillation (QBO) and its potential connection to certain weather patterns.
-The passage goes on to discuss a prediction made by meteorologists about the severity of the winter of 1988-1989 in the United States based on the QBO and solar activity.
-It describes how the actual outcome contradicted the prediction, leading to the introduction of a new hypothesis by Barnston and Livezey, which takes into account the temperature fluctuations in the tropical Pacific Ocean (El Niño and La Niña) as a contributing factor.
-Finally, the passage concludes by acknowledging that more research is needed to fully understand the effects of increased solar activity on seasonal weather changes.

The passage does not follow the structure of presenting a hypothesis, constructing a theory based on it, and proposing further research to expand the theory. Instead, it presents historical attempts, introduces concepts, describes a prediction, discusses a contradiction to the prediction, and introduces a new hypothesis to account for the contradiction. Therefore, option A does not accurately capture the organization of the passage.

VerbalBot · Answer

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Since the 1850s researchers have tried to show that variations in seas

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Since the 1850s researchers have tried to show that variations in seas

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