Oceanographer: To substantially reduce

Answer choices

1. A

   Out of Scope Comparison: thoroughly4% picked this

   Carbon dioxide will dissolve much more thoroughly if it is pumped into cold water than it will if it

   The author has committed to the idea that the CO2 pumped into the deep ocean would dissolve there, but that's it. There's no comparison between how thoroughly it dissolves here vs. there.

   4%
2. B

   Negation Doesn't Weaken12% picked this

   Evaporation of warmer ocean water near an ocean's surface does not generally release into the atmosphere large amounts of the carbon dioxide

   This answer has that lovable Defender form; it's ruling out an idea using "not / no" language. But if we negate this, does it weaken to say, "The water that evaporates near the surface generally does release large amounts of CO2 from what ever CO2 is dissolved in that evaporating water"? At first this seems pretty tempting. If we wanted to argue that this plan wasn't going to work, then being able to say that "large amounts of CO2 were going be released into the atmosphere" definitely sounds up our alley. But this is talking about CO2 evaporating from the surface of the ocean. That doesn't have anything to do with the Plan we're evaluating. The plan is to pump CO2 deep into the cold depths of the sea. Supposedly it won't make it to the surface and evaporate until a few centuries from now. The author's plan implicitly accepts that this is a "short-term" fix, that allows us to reduce atmospheric CO2 for a few hundred years.

   12%
3. C

   Correct73% picked this

   Carbon dioxide dissolved in cool, dense water in ocean depths will not escape back into Earth's atmosphere a long time before the water in

   Why this is right

   This has the lovable Defender ruling-out "not". If we negate it, does it weaken to say, "Hey, author --- the CO2 we pump into the cold, dense depths will escape back into the atmosphere way before the cold water mixes with the warm surface water". Sure, that weakens! The author's whole plan is about selling us a few centuries' worth of not having to worry about this CO22. Pump it down there now, and the cold water won't mix with the surface for a few centuries. The author was assuming that "if the cold water hasn't mixed with the warm, then the CO2 is still trapped". And if you believe that the CO2 is trapped until the cold mixes with the warm, then you synonymously believe that the CO2 won't escape back into the atmosphere long before the cold has mixed with the warm.

   Skill tested: Necessary Assumption · how this choice captures the argument's function is the move to repeat next time.

   73%
4. D

   Too Strong: main role5% picked this

   It is the density of the water in the ocean depths that plays the main role in the

   The author is selling us on a plan to pump CO2 down to the cold, dense depths of the ocean in order to trap it there. There is no starring role there. Maybe the coldness of the water is the main reason it's trapped. Maybe the density is. Maybe the depth is. Maybe something else. The author's argument wouldn't change whether density was the biggest reason or smallest reason CO2 was trapped.

   5%
5. E

   Reversed Logic If-Conclusion6% picked this

   Carbon dioxide should be pumped into ocean depths to reduce the amount of carbon dioxide in the atmosphere only if the carbon dioxide pumped

   When we see conditional answers on Necessary Assumption, we don't want to negate them. Instead, we should just look at them as a Left Side → Right Side reasoning move and ask ourselves whether that matches a move the author made. (Usually correct answers that are conditionals are written in contrapositive form) Here, we'd see the Conditional Indicator "only if" which always introduces the Right Side (necessary) idea: CO2 should be pumped the CO2 pumped into ocean depths → there would be to reduce atmosph CO2 trapped for 100's This does not match any of the Author's reasoning moves. Authors go from Evidence to Conclusion. But this answer is going from Conclusion on the left to an idea from the Evidence on the right. Putting the Conclusion on the left side of the arrow is always wrong.

   6%