#10 - The more sunlight our planet reflects back into space

[Administrator]

Please post below with any questions!

[lll7]

This was one of the questions that surprisingly gave me trouble on the test. I originally selected the right answer, C, and even marked it on my scantron, but I gave into my doubts unfortunately, and chose answer choice D.

How can I avoid making this mistake on the December LSAT? Why is C the correct answer, why is D wrong? I sort of get it but I would appreciate getting an expert opinion.

[lll7]

I see why C is right. It bolsters the connection b/w the premise and the conclusion by providing another reason why when the Earth's surface has less snow and ice, and so the land and ocean water isn't covered w/ snow, the atmosphere is more likely to be warmer. The reason I saw potential in D is b/c I equated 'passage of sunlight' to light not being reflected out into the atmosphere, and if most of global temperature's heat is determined by how much sunlight it can retain, I thought this would strengthen the conclusion that w/ more snow and ice, the cooler the atmosphere will become because this is the most significant factor.

Does that makes sense?

[Jonathan Evans]

III7,

I understand your thought process but invite you to read over your own explanation because it might shed light on a problem you encounter on the test. On Strengthen and Weaken questions, you are looking for new evidence that directly impacts the validity of the conclusion by addressing the missing information. In a Strengthen question, the credited response could be in the form of a supporter (bringing new and different evidence to back up a claim, shoring up the integrity of the evidence provided, etc.) or a defender (ruling out an unwanted possibility that would weaken the claim).

In your explanation of your reason for selecting answer choice D, you should notice the additional assumptions you make to "shoehorn" in answer choice D into the argument. When you have to jump through a couple new hoops to make an answer work, it's not the right answer. Recall the directions for the Logical Reasoning section:

"You should not make assumptions that are by commonsense standards implausible, superfluous, or incompatible with the passage."

If you find yourself saying something to the effect of, "well man, I can kinda see how this one would work if we also knew these other three things," then you have found an incorrect answer!

With respect to answer choice C, you have accurately described the reason why it is correct: it provides an additional premise that supports the claim that the amount of snow and ice is inversely proportional to global temperature.

[studytime]

Why is answer choice A wrong?

I was focusing on the argument that the more surface area is covered by snow, the colder the global atmosphere - I may have over-interpreted this to mean that the "strengthened" argument would demonstrate that there could even be a multiplier effect in regards to how snow made for MUCH colder weather. My reasoning was that if more snow is on the ground, the atmosphere gets colder, which in turn creates the conditions which will further make it even colder, since there will then be more snow. I recognized though that this answer choice would fit a lot better if low-temperature atmospheric conditions had been a sufficient condition, rather than a necessary condition, for snow. It seemed more relevant though than the other answer choices. If the answer choice had been "the lower the temperature atmospheric conditions, the more likely even more snow would fall" - would this have been any better of an answer choice?

I don't understand why C is a stronger answer. It seems to almost weaken one of the premises in terms of its support for the argument: it is stated that ocean water and land without snow DON'T reflect much sunlight back into space--we can infer from the other premise that while they do not aid in cooling the global temperature, they wouldn't hinder it. However, once they are seen to have a warming effect, they then would seem to hinder the cooling of global temperature, especially as we do not know how much warmer they can make things.

Can anyone help me out here?

[Jonathan Evans]

Hi, Studytime,

Let's make a quick rundown of the components of this argument and the task we're trying to accomplish:

P1: The more sunlight reflected back into space, the cooler the planet tends to become.

P2: Snow and ice reflect more sunlight into space than do ocean and land uncovered by snow.

C: The more surface covered by snow and ice, the cooler the atmosphere will become.

Task: Provide support for the claim that "The more surface covered by snow and ice, the cooler the atmosphere will become."

We already have some support as you noted. However, you must be careful on Strengthen questions to understand that your prediction (even if it's a great prediction!) will not always match up exactly with the credited response. There are often a couple different ways to accomplish this goal. As I noted in my post above, you could support the conclusion by providing new (and different) evidence that backs up the claim. You could also defend the validity of the conclusion by ruling out an unwanted possibility.

Let's consider the two answer choices that you've identified. Answer Choice (A) kinda takes you on a fun journey into a tangential consideration. So what if we need low temperatures to have clouds that generate snow? Does this bolster our point that "The more surface covered by snow and ice, the cooler the atmosphere will become"? No. While it may seem relevant, it does not address the central claim directly. Further, even if the "low atmospheric temperatures" were sufficient to know that more clouds would be formed leading to more snow, you would not really be addressing the gap between the premises and the conclusion. To make this information work for you, you'd have to introduce a rather circular assumption, that you will have the lower temperatures sufficient to generate more clouds to generate more snow.

Instead, you need to address this gap, which involves the other part of the equation that we thus far have not addressed, i.e. the effect of the rest of the non-snow/ice covered land on global atmosphere.

Consider for instance: what if non-snow/ice covered land has some other method of cooling the planet even more than by reflecting sunlight back into space? What would the effect on the conclusion be then? It would be a dramatically weaker conclusion, even given the truth of the premises provided.

Answer Choice (C) addresses this gap by stating that this non-snow/ice covered land in fact exacerbate a warming atmosphere, giving strong new support for the claim that "The more surface covered by snow and ice, the cooler the atmosphere will become" because clearly with less surface covered by snow and ice, you will not only experience less cooling from less snow/ice but also more warming from the rest of the land/ocean area.

[MBG13]

For this question, I was stuck between (C) and (E) and ended up incorrectly picking (E) because I thought it more directly dealt with the conclusion than (C).

Can someone explain E and give strategies on how to avoid picking the wrong of two answers in the future?

[Emily Haney-Caron]

Hi MBG13,

Thanks for the question! E is wrong because it just isn't at all relevant; lighter-colored vs. darker-colored soil just don't come into play at all in the argument here. I think a big key for you in terms of avoiding incorrect answers is going to be coming up with a prephrase before you even look at the answer choices. Then, you'll have an idea of what you're looking for, which will help you avoid the incorrect answers. The other thing that I will suggest is to know your question types well, and the PowerScore approach to each. Different question types will have different common types of wrong answers the test makers use to bait you; knowing those, and spotting the type of question you're completing, will help you avoid common pitfalls.

[mN2mmvf]

I found (C) confusing because it doesn't specify that it's talking about ocean water and land *without snow cover.* It instead talks about land "heated by sunlight," which means that that land may or may not have snow on it. If it had snow on it, then it would not strengthen the argument.

I chose (D) because it would defend against the possibility that the reflection of sunlight back into space might have an extremely small impact on the temperate of the global atmosphere.

Can you help explain where I went wrong?

[Adam Tyson]

Looks to me like D might actually weaken the argument, mN2mmvf. If the atmosphere gets most of its heat from sunlight passing through, then reflected sunlight, as from snow and ice, would have twice the impact as non-reflected sunlight, because it passes through on the way down to the surface and then passes through again as it is reflected back up. More reflected sunlight should have a warming effect, if D is true. Then again, I might be reading too much into it.

If we were to agree that "land heated by sunlight" includes land covered in snow and ice, you would have to also agree that the land covered by snow and ice gets heated less than uncovered land, because at least some of the sunlight that would otherwise heat that land is being reflected back by the snow and ice. This would be the same with ocean ice - the water underneath is heated less than open water because not all of the sunlight is getting through. That's why C works - it strengthens the idea that covering up more of the surface leads to a colder atmosphere because it means the land and water under that snow and ice are being warmed less than they otherwise would.

I hope that sheds some light on things!