Q9

[logicfiend]

Q asks "Which one of the following most accurately characterizes what the author of the passage means by a 'minor' volcanic eruption?"

We know volcanic eruptions leave behind a "veil of fine dust and sulfuric acid droplets" (3). We can infer that a minor volcanic eruption would release/leave less dust and sulfuric acid droplets than a major eruption would.

This is supported by the different impacts that minor and major eruptions have had on the climate: "minor eruptions have no discernible effect on temperature. And major, dust-spitting explosions" can have greater impacts, at least according to one theory.

Therefore, D best fits with the provided information. A minor eruption would be characterized as an eruption with leaving a small amount of debris, or dust, in the environment.

Rest of the answers:

A) nothing about lava (more or less) is mentioned in the passage to differentiate minor/major eruptions.

B) minor eruption has less of an impact than Krakatua or El Chichon did—but is this how the author meant to characterize the word? Likely a minor eruption would have less of an impact, but this isn't how it was meant to be defined.

C) Combines a bunch of things from the passage about regional temp and hemisphere conditions. None of these are meant to explain "minor" explosions as in the passage.

E) eruption causes avg temp to drop by less than half a degree—a few problems with this answer choice. First, we don't know if there will be any kind of drop at all with a minor eruption. But also, what defines the eruption is what may cause temperature change, which is the amount of dust, not the temperature change itself.

Please correct anything that is wrong, thanks!

[ohthatpatrick]

Great post, thanks!

This is a weird question, since (B), (C), and (E) seem pretty "true".

(A) seems super reasonable, though we definitely have no support for the volume of lava of any of these eruptions.

(C) is probably wrong since we heard that minor eruptions have no discernible effect (how can you "mask" no effect?)

But (B) and (E) feel like fair comparisons. As you said, (E) seems fishy because minor eruptions don't cause ANY drop. However, technically, no drop in temp IS less than a half-degree centigrade drop.

You nailed it when you said we need to really think about the language of the question stem. Does the author mean to use "minor" to make a specific comparison to Krakatau or El Chichon? Probably not. Does the author mean to put a "causes a less-than-half-degree drop" in our brain? Probably not, because minor eruptions cause nothing.

We need the closest thing to "no discernible effect", negligible, not gonna affect climate.

(D) is far from great, but it at least gets at the generic concept of "less likely to influence climate", by naming the specific mechanism by which MAJOR eruptions DO affect climate: debris in the atmosphere.

I'm not a fan of this question. But I am of your explanation.