1. Which one of the following most accurately expresses the main idea of the passage?(A) The effect of volcanic eruptions on regional temperature is greater than it was once thought to be.
(B) The effect of volcanic eruptions on regional temperature is smaller than the effect of volcanic eruptions on global temperature.
(C) The effect of volcanic eruptions on global temperature appears to be greater than was previously supposed.
(D) Volcanic eruptions appear not to have the significant effect on global temperature they were once thought to have but might have a significant effect on regional temperature.
(E) Researchers tended to overestimate the influence of volcanic eruptions on global temperature because they exaggerated the effect of cyclical weather phenomena in making their calculations.
2. Not taking the effects of El Niño into account when figuring the effect of volcanic eruptions on Earth’s climate is most closely analogous to not taking into account the(A) weight of a package as a whole when determining the weight of its contents apart from the packing material
(B) monetary value of the coins in a pile when counting the number of coins in the pile
(C) magnification of a lens when determining the shape of an object seen through the lens
(D) number of false crime reports in a city when figuring the average annual number of crimes committed in that city
(E) ages of new immigrants to a country before attributing a change in the average of the country’s population to a change in the number of births
3. The passage indicates that each of the following can be an effect of the El Niño phenomenon EXCEPT:(A) making the cooling effect of a volcanic eruption appear to be more pronounced than it actually is
(B) making the cooling effect of a volcanic eruption appear to be less pronounced than it actually is
(C) increasing atmospheric temperature through cyclic warming of equatorial waters
(D) initiating a feedback loop that masks cooling brought about by an eruption
(E) confounding the evidence for a volcano climate connection
4. Which one of the following most accurately characterizes what the author of the passage means by a “minor” volcanic eruption (line 30)?(A) an eruption that produces less lava than either Krakatau or El Chichón did
(B) an eruption that has less of an effect on global temperature than either Krakatau or El Chichón did
(C) an eruption whose effect on regional temperature can be masked by conditions in the hemisphere of the eruption
(D) an eruption that introduces a relatively small amount of debris into the atmosphere
(E) an eruption that causes average temperature in the hemisphere of the eruption to drop by less than half a degree centigrade
5. To which one of the following situations would the concept of a feedback loop, as it is employed in the passage, be most accurately applied?(A) An increase in the amount of decaying matter in the soil increases the amount of nutrients in the soil, which increases the number of plants, which further increases the amount of decaying matter in the soil.
(B) An increase in the number of wolves in an area decreases the number of deer, which decreases the grazing of shrubs, which increases the amount of food available for other animals, which increases the number of other animals in the area.
(C) An increase in the amount of rain in an area increases the deterioration of the forest floor, which makes it harder for wolves to prey on deer, which increases the number of deer, which gives wolves more opportunities to prey upon deer.
(D) An increase in the amount of sunlight on the ocean increases the ocean temperature, which increases the number of phytoplankton in the ocean, which decreases the ocean temperature by blocking sunlight.
(E) As increase in the number of outdoor electric lights in an area increases the number of insects in the area, which increases the number of bats in the area, which decreases the number of insects in the area, which decreases the number of bats in the area.
6. The author of the passage would be most likely to agree with which one of the following hypotheses?(A) Major volcanic eruptions sometimes cause average temperature in the hemisphere of the eruption to drop by more than a degree centigrade.
(B) Major volcanic eruptions can induce the El Niño phenomenon when it otherwise might not occur.
(C) Major volcanic eruptions do not directly cause unusually cold summers.
(D) The climatic effects of minor volcanic eruptions differ from those of major eruptions only in degree.
(E) El Niño has no discernible effect on average hemispheric temperature.
7. The information in the passage provides the LEAST support for which one of the following claims?(A) Major volcanic eruptions have a discernible effect on global temperature.
(B) The effect of major volcanic eruptions on global temperature is smaller than was previously thought.
(C) Major volcanic eruptions have no discernible effect on regional temperature.
(D) Minor volcanic eruptions have no discernible effect on temperature in the hemisphere in which they occur.
(E) Minor volcanic eruptions have no discernible effect on temperature in the hemisphere opposite the hemisphere of the eruption.
8. The primary purpose of the last paragraph of the passage is to(A) describe how the “year without a summer” differs from other examples of climatic feedback loops
(B) account for the relatively slight hemispheric cooling effect of a major volcanic eruption
(C) explain how regional climatic conditions can be significantly affected by a small drop in temperature
(D) indicate how researchers are sometimes led to overlook the effects of El Niño on regional temperature
(E) suggest a modification to the current model of how feedback loops produce changes in regional temperature