SAT Practice Test 6
'Hiatus in rise of Earth's surface air temperature likely temporary' - Between 1998 and 2012, climate scientists observed a slowdown in the rate at which the Earth's surface air temperature was rising. While the rise in global mean surface air temperature has continued, between 1998 and 2012 the increase was approximately one third of that from 1951 to 2012.
- This trend — referred to as a "global warming hiatus" — has sparked a lot of debate and given rise to a reasonable question: Is global warming coming to a halt?
- According to Norman Loeb, an atmospheric scientist at NASA's Langley Research Center in Hampton, Virginia, and the principal investigator of a space-borne sensor called the Clouds and Earth's Radiant Energy System, or CERES, the answer is almost certainly no.
- "Heating is still going on," he said. "It's just not in terms of the surface air temperature."
- Loeb explained the science behind that statement Tuesday, Aug. 5, during a talk at NASA Langley titled "The Recent Pause in Global Warming: A Temporary Blip or Something More Permanent?"
- Though Loeb believes there are a handful of short-term factors that drive changes in surface air temperature, like the El Niño and La Niña phenomena that cause temperature fluctuations in the tropical eastern Pacific approximately every two years, he thinks there is a longer term factor that is a significant and overlooked contributor.
- "The Pacific Decadal Oscillation affects surface temperature," Loeb said. "It's a pattern of temperature shifts, primarily over the Pacific, that occurs about every 20 or 30 years."
- Historically, those shifts have coincided with changes in surface temperature.
- "The Pacific Decadal Oscillation has a very distinctive pattern. During the positive phase, surface temperature rises more rapidly," he said. "During the negative phase, the rate of temperature increase slows down, hence a hiatus. It's very compelling when you see the actual observations."
- Loeb showed measurements during his talk demonstrating steady increases in surface air temperature from 1920 to 1940 and again from 1976 to 2000, periods when the decadal oscillation was in a positive phase. From 1940 to 1975, and again beginning in 2001, temperatures leveled out in concert with negative oscillation phases.
- Surface air temperatures have increased by approximately 1.4 degrees Fahrenheit since the early 20th century. On this timescale, the hiatuses look like short ledges along a graph of global average surface air temperature with an otherwise steep upward slope.
- "You can't just look at short periods of time," Loeb said. "You have to look at the record over a long period of time to see the pattern. There will be natural fluctuations at shorter time scales, but we really shouldn't conclude that that's a change and global warming is going away."
- Even as surface air temperatures are currently holding relatively steady, Loeb believes there's still another issue to take into consideration.
- "Observations are showing us the planet is still taking up heat, but it is just showing up in a different place," he said.
- That different place is the ocean.
- In other words, as humans and nature continue to apply pressure to the Earth's climate through increases in carbon dioxide and other greenhouse gases, temperatures are still rising. But as the Pacific Decadal Oscillation briefly tames temperatures at the planet's surface, the oceans are where the real heating is happening.
- "If you add extra heat to the Earth system, approximately 93 percent of that extra heat ends up stored in the ocean, and the ocean is very deep," Loeb said. "When we look at air temperature, we are just looking at the surface. There's a whole deep ocean where heat can be stored."
- Scientists are studying ocean temperatures with instruments known as “Argo floats.” These instruments drift freely throughout the world’s oceans, collecting temperature and salinity measurements to a depth of around 6000 feet. The floats rise to the surface and transmit their data to a satellite every 10 days. Currently, more than 3,600 Argo floats distributed in the planet's oceans show that the oceans are taking up heat over time, according to Loeb.
- Combine that with data from NASA's CERES sensor, which shows the rate of heat uptake by the whole planet is nearly constant, and it becomes clear that the planet is still warming, even as the increase in surface air temperatures lull temporarily.
- "Heat can be redistributed," Loeb said of the energy. "Changes in the circulation patterns in the ocean and atmosphere will result in redistribution of the heat — and that is what is going on during the different phases of this [Pacific Decadal Oscillation]."
- Loeb and the overwhelming majority of his fellow climate scientists argue that as humans continue to pump carbon dioxide and other greenhouse gases into the atmosphere at unprecedented rates — atmospheric carbon dioxide measurements hit 400 parts per million in May 2013 — climate change will continue. Current estimates have global average surface air temperatures rising anywhere from approximately 3 to 8.5 degrees Fahrenheit by the year 2100, depending on how much carbon dioxide and other greenhouse gases are added to the atmosphere and accounting for uncertainty in predictions.
- But even given the scientific evidence that points toward definite warming, and data that shows that the last three decades have been the hottest on record, each one a little bit warmer than the last, Loeb encourages the scientific community to improve its observations and models of the climate system, and to discuss the science objectively and rationally.
- "It’s okay to be skeptical," he said. "Scientists are skeptical by nature. But at the same time, we need to be reasonable.”
In paragraph 5, "Blip" most nearly means
Answer 1: The word "anomaly" and the word "blip" go hand-in-hand, especially when you read the paragraph and see the word "Temporary" connected to blip then contrasted with "permanent."
'Hiatus in rise of Earth's surface air temperature likely temporary' - Between 1998 and 2012, climate scientists observed a slowdown in the rate at which the Earth's surface air temperature was rising. While the rise in global mean surface air temperature has continued, between 1998 and 2012 the increase was approximately one third of that from 1951 to 2012.
- This trend — referred to as a "global warming hiatus" — has sparked a lot of debate and given rise to a reasonable question: Is global warming coming to a halt?
- According to Norman Loeb, an atmospheric scientist at NASA's Langley Research Center in Hampton, Virginia, and the principal investigator of a space-borne sensor called the Clouds and Earth's Radiant Energy System, or CERES, the answer is almost certainly no.
- "Heating is still going on," he said. "It's just not in terms of the surface air temperature."
- Loeb explained the science behind that statement Tuesday, Aug. 5, during a talk at NASA Langley titled "The Recent Pause in Global Warming: A Temporary Blip or Something More Permanent?"
- Though Loeb believes there are a handful of short-term factors that drive changes in surface air temperature, like the El Niño and La Niña phenomena that cause temperature fluctuations in the tropical eastern Pacific approximately every two years, he thinks there is a longer term factor that is a significant and overlooked contributor.
- "The Pacific Decadal Oscillation affects surface temperature," Loeb said. "It's a pattern of temperature shifts, primarily over the Pacific, that occurs about every 20 or 30 years."
- Historically, those shifts have coincided with changes in surface temperature.
- "The Pacific Decadal Oscillation has a very distinctive pattern. During the positive phase, surface temperature rises more rapidly," he said. "During the negative phase, the rate of temperature increase slows down, hence a hiatus. It's very compelling when you see the actual observations."
- Loeb showed measurements during his talk demonstrating steady increases in surface air temperature from 1920 to 1940 and again from 1976 to 2000, periods when the decadal oscillation was in a positive phase. From 1940 to 1975, and again beginning in 2001, temperatures leveled out in concert with negative oscillation phases.
- Surface air temperatures have increased by approximately 1.4 degrees Fahrenheit since the early 20th century. On this timescale, the hiatuses look like short ledges along a graph of global average surface air temperature with an otherwise steep upward slope.
- "You can't just look at short periods of time," Loeb said. "You have to look at the record over a long period of time to see the pattern. There will be natural fluctuations at shorter time scales, but we really shouldn't conclude that that's a change and global warming is going away."
- Even as surface air temperatures are currently holding relatively steady, Loeb believes there's still another issue to take into consideration.
- "Observations are showing us the planet is still taking up heat, but it is just showing up in a different place," he said.
- That different place is the ocean.
- In other words, as humans and nature continue to apply pressure to the Earth's climate through increases in carbon dioxide and other greenhouse gases, temperatures are still rising. But as the Pacific Decadal Oscillation briefly tames temperatures at the planet's surface, the oceans are where the real heating is happening.
- "If you add extra heat to the Earth system, approximately 93 percent of that extra heat ends up stored in the ocean, and the ocean is very deep," Loeb said. "When we look at air temperature, we are just looking at the surface. There's a whole deep ocean where heat can be stored."
- Scientists are studying ocean temperatures with instruments known as “Argo floats.” These instruments drift freely throughout the world’s oceans, collecting temperature and salinity measurements to a depth of around 6000 feet. The floats rise to the surface and transmit their data to a satellite every 10 days. Currently, more than 3,600 Argo floats distributed in the planet's oceans show that the oceans are taking up heat over time, according to Loeb.
- Combine that with data from NASA's CERES sensor, which shows the rate of heat uptake by the whole planet is nearly constant, and it becomes clear that the planet is still warming, even as the increase in surface air temperatures lull temporarily.
- "Heat can be redistributed," Loeb said of the energy. "Changes in the circulation patterns in the ocean and atmosphere will result in redistribution of the heat — and that is what is going on during the different phases of this [Pacific Decadal Oscillation]."
- Loeb and the overwhelming majority of his fellow climate scientists argue that as humans continue to pump carbon dioxide and other greenhouse gases into the atmosphere at unprecedented rates — atmospheric carbon dioxide measurements hit 400 parts per million in May 2013 — climate change will continue. Current estimates have global average surface air temperatures rising anywhere from approximately 3 to 8.5 degrees Fahrenheit by the year 2100, depending on how much carbon dioxide and other greenhouse gases are added to the atmosphere and accounting for uncertainty in predictions.
- But even given the scientific evidence that points toward definite warming, and data that shows that the last three decades have been the hottest on record, each one a little bit warmer than the last, Loeb encourages the scientific community to improve its observations and models of the climate system, and to discuss the science objectively and rationally.
- "It’s okay to be skeptical," he said. "Scientists are skeptical by nature. But at the same time, we need to be reasonable.”
Which choice provides the best evidence for the answer to the previous question?
Answer 4: it is paragraph 3 where we find out what CERES actually does.
'Hiatus in rise of Earth's surface air temperature likely temporary' - Between 1998 and 2012, climate scientists observed a slowdown in the rate at which the Earth's surface air temperature was rising. While the rise in global mean surface air temperature has continued, between 1998 and 2012 the increase was approximately one third of that from 1951 to 2012.
- This trend — referred to as a "global warming hiatus" — has sparked a lot of debate and given rise to a reasonable question: Is global warming coming to a halt?
- According to Norman Loeb, an atmospheric scientist at NASA's Langley Research Center in Hampton, Virginia, and the principal investigator of a space-borne sensor called the Clouds and Earth's Radiant Energy System, or CERES, the answer is almost certainly no.
- "Heating is still going on," he said. "It's just not in terms of the surface air temperature."
- Loeb explained the science behind that statement Tuesday, Aug. 5, during a talk at NASA Langley titled "The Recent Pause in Global Warming: A Temporary Blip or Something More Permanent?"
- Though Loeb believes there are a handful of short-term factors that drive changes in surface air temperature, like the El Niño and La Niña phenomena that cause temperature fluctuations in the tropical eastern Pacific approximately every two years, he thinks there is a longer term factor that is a significant and overlooked contributor.
- "The Pacific Decadal Oscillation affects surface temperature," Loeb said. "It's a pattern of temperature shifts, primarily over the Pacific, that occurs about every 20 or 30 years."
- Historically, those shifts have coincided with changes in surface temperature.
- "The Pacific Decadal Oscillation has a very distinctive pattern. During the positive phase, surface temperature rises more rapidly," he said. "During the negative phase, the rate of temperature increase slows down, hence a hiatus. It's very compelling when you see the actual observations."
- Loeb showed measurements during his talk demonstrating steady increases in surface air temperature from 1920 to 1940 and again from 1976 to 2000, periods when the decadal oscillation was in a positive phase. From 1940 to 1975, and again beginning in 2001, temperatures leveled out in concert with negative oscillation phases.
- Surface air temperatures have increased by approximately 1.4 degrees Fahrenheit since the early 20th century. On this timescale, the hiatuses look like short ledges along a graph of global average surface air temperature with an otherwise steep upward slope.
- "You can't just look at short periods of time," Loeb said. "You have to look at the record over a long period of time to see the pattern. There will be natural fluctuations at shorter time scales, but we really shouldn't conclude that that's a change and global warming is going away."
- Even as surface air temperatures are currently holding relatively steady, Loeb believes there's still another issue to take into consideration.
- "Observations are showing us the planet is still taking up heat, but it is just showing up in a different place," he said.
- That different place is the ocean.
- In other words, as humans and nature continue to apply pressure to the Earth's climate through increases in carbon dioxide and other greenhouse gases, temperatures are still rising. But as the Pacific Decadal Oscillation briefly tames temperatures at the planet's surface, the oceans are where the real heating is happening.
- "If you add extra heat to the Earth system, approximately 93 percent of that extra heat ends up stored in the ocean, and the ocean is very deep," Loeb said. "When we look at air temperature, we are just looking at the surface. There's a whole deep ocean where heat can be stored."
- Scientists are studying ocean temperatures with instruments known as “Argo floats.” These instruments drift freely throughout the world’s oceans, collecting temperature and salinity measurements to a depth of around 6000 feet. The floats rise to the surface and transmit their data to a satellite every 10 days. Currently, more than 3,600 Argo floats distributed in the planet's oceans show that the oceans are taking up heat over time, according to Loeb.
- Combine that with data from NASA's CERES sensor, which shows the rate of heat uptake by the whole planet is nearly constant, and it becomes clear that the planet is still warming, even as the increase in surface air temperatures lull temporarily.
- "Heat can be redistributed," Loeb said of the energy. "Changes in the circulation patterns in the ocean and atmosphere will result in redistribution of the heat — and that is what is going on during the different phases of this [Pacific Decadal Oscillation]."
- Loeb and the overwhelming majority of his fellow climate scientists argue that as humans continue to pump carbon dioxide and other greenhouse gases into the atmosphere at unprecedented rates — atmospheric carbon dioxide measurements hit 400 parts per million in May 2013 — climate change will continue. Current estimates have global average surface air temperatures rising anywhere from approximately 3 to 8.5 degrees Fahrenheit by the year 2100, depending on how much carbon dioxide and other greenhouse gases are added to the atmosphere and accounting for uncertainty in predictions.
- But even given the scientific evidence that points toward definite warming, and data that shows that the last three decades have been the hottest on record, each one a little bit warmer than the last, Loeb encourages the scientific community to improve its observations and models of the climate system, and to discuss the science objectively and rationally.
- "It’s okay to be skeptical," he said. "Scientists are skeptical by nature. But at the same time, we need to be reasonable.”
The principal rhetorical purpose for the phrase in paragraph 23 "Scientists are skeptical by nature. But at the same time, we need to be reasonable." is to
Answer 2: answers one and three are far too vague and answer four does not compute because Republicans are not mentioned in any way within the passage.
'Hiatus in rise of Earth's surface air temperature likely temporary' - Between 1998 and 2012, climate scientists observed a slowdown in the rate at which the Earth's surface air temperature was rising. While the rise in global mean surface air temperature has continued, between 1998 and 2012 the increase was approximately one third of that from 1951 to 2012.
- This trend — referred to as a "global warming hiatus" — has sparked a lot of debate and given rise to a reasonable question: Is global warming coming to a halt?
- According to Norman Loeb, an atmospheric scientist at NASA's Langley Research Center in Hampton, Virginia, and the principal investigator of a space-borne sensor called the Clouds and Earth's Radiant Energy System, or CERES, the answer is almost certainly no.
- "Heating is still going on," he said. "It's just not in terms of the surface air temperature."
- Loeb explained the science behind that statement Tuesday, Aug. 5, during a talk at NASA Langley titled "The Recent Pause in Global Warming: A Temporary Blip or Something More Permanent?"
- Though Loeb believes there are a handful of short-term factors that drive changes in surface air temperature, like the El Niño and La Niña phenomena that cause temperature fluctuations in the tropical eastern Pacific approximately every two years, he thinks there is a longer term factor that is a significant and overlooked contributor.
- "The Pacific Decadal Oscillation affects surface temperature," Loeb said. "It's a pattern of temperature shifts, primarily over the Pacific, that occurs about every 20 or 30 years."
- Historically, those shifts have coincided with changes in surface temperature.
- "The Pacific Decadal Oscillation has a very distinctive pattern. During the positive phase, surface temperature rises more rapidly," he said. "During the negative phase, the rate of temperature increase slows down, hence a hiatus. It's very compelling when you see the actual observations."
- Loeb showed measurements during his talk demonstrating steady increases in surface air temperature from 1920 to 1940 and again from 1976 to 2000, periods when the decadal oscillation was in a positive phase. From 1940 to 1975, and again beginning in 2001, temperatures leveled out in concert with negative oscillation phases.
- Surface air temperatures have increased by approximately 1.4 degrees Fahrenheit since the early 20th century. On this timescale, the hiatuses look like short ledges along a graph of global average surface air temperature with an otherwise steep upward slope.
- "You can't just look at short periods of time," Loeb said. "You have to look at the record over a long period of time to see the pattern. There will be natural fluctuations at shorter time scales, but we really shouldn't conclude that that's a change and global warming is going away."
- Even as surface air temperatures are currently holding relatively steady, Loeb believes there's still another issue to take into consideration.
- "Observations are showing us the planet is still taking up heat, but it is just showing up in a different place," he said.
- That different place is the ocean.
- In other words, as humans and nature continue to apply pressure to the Earth's climate through increases in carbon dioxide and other greenhouse gases, temperatures are still rising. But as the Pacific Decadal Oscillation briefly tames temperatures at the planet's surface, the oceans are where the real heating is happening.
- "If you add extra heat to the Earth system, approximately 93 percent of that extra heat ends up stored in the ocean, and the ocean is very deep," Loeb said. "When we look at air temperature, we are just looking at the surface. There's a whole deep ocean where heat can be stored."
- Scientists are studying ocean temperatures with instruments known as “Argo floats.” These instruments drift freely throughout the world’s oceans, collecting temperature and salinity measurements to a depth of around 6000 feet. The floats rise to the surface and transmit their data to a satellite every 10 days. Currently, more than 3,600 Argo floats distributed in the planet's oceans show that the oceans are taking up heat over time, according to Loeb.
- Combine that with data from NASA's CERES sensor, which shows the rate of heat uptake by the whole planet is nearly constant, and it becomes clear that the planet is still warming, even as the increase in surface air temperatures lull temporarily.
- "Heat can be redistributed," Loeb said of the energy. "Changes in the circulation patterns in the ocean and atmosphere will result in redistribution of the heat — and that is what is going on during the different phases of this [Pacific Decadal Oscillation]."
- Loeb and the overwhelming majority of his fellow climate scientists argue that as humans continue to pump carbon dioxide and other greenhouse gases into the atmosphere at unprecedented rates — atmospheric carbon dioxide measurements hit 400 parts per million in May 2013 — climate change will continue. Current estimates have global average surface air temperatures rising anywhere from approximately 3 to 8.5 degrees Fahrenheit by the year 2100, depending on how much carbon dioxide and other greenhouse gases are added to the atmosphere and accounting for uncertainty in predictions.
- But even given the scientific evidence that points toward definite warming, and data that shows that the last three decades have been the hottest on record, each one a little bit warmer than the last, Loeb encourages the scientific community to improve its observations and models of the climate system, and to discuss the science objectively and rationally.
- "It’s okay to be skeptical," he said. "Scientists are skeptical by nature. But at the same time, we need to be reasonable.”
It can be reasonably inferred from information in the passage that
Answer 3: answer one is too vague, answer to is false, and answer four is not covered in the passage.
Read the following two passages, to answer the associated questions.
A Short Essay on Volcanoes
- A volcano is an opening, in the planet’s surface which allows hot, molten rock, ash and gases to escape from below the surface.
- The name, “volcano” originates from the name Vulcan, a god of fire in Roman mythology. Volcanoes are like giant safety valves that release the pressure that builds up inside the Earth. The Hawaii islands were formed by 5 volcanoes. Classified by the extent of their activity volcanoes are of four types. An ‘active’ volcano is one that erupts regularly. There are about 500 known active volcanoes on Earth, not counting those that lie beneath the sea.
- A ‘dormant’ volcano is one that has not erupted for many years, although there is still some activity deep inside it. An ‘extinct’ volcano is one which has ceased to be active.
- A volcanic eruption occurs when hot rocks and lava burst from a volcano; and geysers and springs are actually just volcanoes that throw boiling water high in the air. They are caused by volcanic heat warming trapped ground water. The liquid rocks inside a volcano are called magma and when it flows out it is called as lava.
- Fresh lava has temperatures from 700 degrees C to 1200’C and glows red-hot to white hot as it flows. The most dangerous volcanic eruption recorded is the eruption of Mount St. Helens in Washington. The tallest volcano in the world is the Ojos del Salado, a volcano in Chile. The world’s largest volcano is the Muano Loa in Hawaii.
- Volcanoes are generally concentrated on the edge of continents, along the island chain, or beneath the sea forming long mountain ranges. A major part of the world’s active volcanoes above sea level encircle the Pacific Ocean forming the “Ring of Fire.”
- Volcanoes can have serious affects on the lands and people around them when they erupt. The destruction they leave in their wake accounts for the total annihilation of the surrounding landscape. Around 2, 00,000 people have lost their lives to volcanic eruptions in the past five hundred years.
- Buildings are destroyed, people are rendered homeless, people are killed, plant and animal life are both destroyed and the poisonous gases that emanate from the volcanoes can cause death and diseases like pneumonia in the people who survive it.
- However not everything associated with the volcanoes is negative. The crust of the earth exists due to?the large volumes of magma that did not erupt but instead cooled below the surface. It results in rich soil which is good for cultivation.
- The volcanic ash that blows out of the volcano increases soil fertility by adding nutrients to the soil. Ground water heated by magma can be tapped for geothermal energy. Most of the metallic minerals like copper, gold, silver, lead and zinc are mined from the magmas found deep within the roots of extinct volcanoes.
- With the increasing studies done by scientists on volcanoes it is becoming possible to gauge the activity level of a volcano. With this information although it might not be possible to prevent the erupting of a volcano at least the massive destruction of lives can be avoided by getting people evacuated in time.
Monitoring Volcanic Gases
- Scientists have long recognized that gases dissolved in magma provide the driving force of volcanic eruptions, but only recently have new techniques permitted routine measurement of different types of volcanic gases released into the atmosphere. Sulfurous volcanic gas and visible steam are usually the first things people notice when they visit an active volcano, for example Mount St. Helens pictured here. A number of other gases also escape sight unseen into the atmosphere through hot fumaroles, active vents, and porous ground surfaces. The gases escape as magma rises toward the surface, when it erupts, and even as it cools and crystallizes below ground.
- A primary objective in gas monitoring is to determine changes in the release of certain gases from a volcano, chiefly carbon dioxide and sulfur dioxide. Such changes can be used with other monitoring information to provide eruption warnings and to improve our understanding of how volcanoes work. In recent years, we have directed increased attention toward volcanic gas emissions because of the newly appreciated hazards they sometimes pose and their effects on the Earth's atmosphere and climate.
- Gases released by most volcanoes are difficult to sample and measure on a regular basis, especially when a volcano becomes restless. Direct sampling of gas requires that scientists visit a hot fumarole or an active vent, usually high on a volcano's flank or within its summit crater. At some volcanoes, gases discharge directly into crater lakes. The remote location of these sampling sites, intense and often hazardous fumes, frequent bad weather, and the potential for sudden eruptions can make regular gas sampling sometimes impossible and dangerous.
- Measuring gases remotely is possible but requires ideal weather and the availability of suitable aircraft or a network of roads around a volcano. Consistent and favorable wind conditions are needed to carry gases from vents and fissures to where they can be measured. In some cases, automated on-site gas monitoring is feasible. Under corrosive conditions, only a few sensors are available, however, for continuously recording the concentrations of specific gases.
- Scientists face yet another challenge--acid gases, like SO2, easily dissolve in water. Thus, volcanoes with abundant surface or subsurface water can prevent scientists from measuring the emission of acid gases as magma rises toward the surface and even after explosive eruptions. Because CO2 is is less likely to be masked by the presence of water, measuring it when a volcano first becomes restless and between eruptions may be important for determining whether significant magma degassing is occurring.
The author of passage 1 most likely believes that
Answer 2: The writer distinguishes the known types of volcanoes, thus negating the response about them destroying everything in their path. Answer 1 is too vague as is Answer 4. That leaves Answer 2.
A Short Essay on Volcanoes
- A volcano is an opening, in the planet’s surface which allows hot, molten rock, ash and gases to escape from below the surface.
- The name, “volcano” originates from the name Vulcan, a god of fire in Roman mythology. Volcanoes are like giant safety valves that release the pressure that builds up inside the Earth. The Hawaii islands were formed by 5 volcanoes. Classified by the extent of their activity volcanoes are of four types. An ‘active’ volcano is one that erupts regularly. There are about 500 known active volcanoes on Earth, not counting those that lie beneath the sea.
- A ‘dormant’ volcano is one that has not erupted for many years, although there is still some activity deep inside it. An ‘extinct’ volcano is one which has ceased to be active.
- A volcanic eruption occurs when hot rocks and lava burst from a volcano; and geysers and springs are actually just volcanoes that throw boiling water high in the air. They are caused by volcanic heat warming trapped ground water. The liquid rocks inside a volcano are called magma and when it flows out it is called as lava.
- Fresh lava has temperatures from 700 degrees C to 1200’C and glows red-hot to white hot as it flows. The most dangerous volcanic eruption recorded is the eruption of Mount St. Helens in Washington. The tallest volcano in the world is the Ojos del Salado, a volcano in Chile. The world’s largest volcano is the Muano Loa in Hawaii.
- Volcanoes are generally concentrated on the edge of continents, along the island chain, or beneath the sea forming long mountain ranges. A major part of the world’s active volcanoes above sea level encircle the Pacific Ocean forming the “Ring of Fire.”
- Volcanoes can have serious affects on the lands and people around them when they erupt. The destruction they leave in their wake accounts for the total annihilation of the surrounding landscape. Around 2, 00,000 people have lost their lives to volcanic eruptions in the past five hundred years.
- Buildings are destroyed, people are rendered homeless, people are killed, plant and animal life are both destroyed and the poisonous gases that emanate from the volcanoes can cause death and diseases like pneumonia in the people who survive it.
- However not everything associated with the volcanoes is negative. The crust of the earth exists due to?the large volumes of magma that did not erupt but instead cooled below the surface. It results in rich soil which is good for cultivation.
- The volcanic ash that blows out of the volcano increases soil fertility by adding nutrients to the soil. Ground water heated by magma can be tapped for geothermal energy. Most of the metallic minerals like copper, gold, silver, lead and zinc are mined from the magmas found deep within the roots of extinct volcanoes.
- With the increasing studies done by scientists on volcanoes it is becoming possible to gauge the activity level of a volcano. With this information although it might not be possible to prevent the erupting of a volcano at least the massive destruction of lives can be avoided by getting people evacuated in time.
Monitoring Volcanic Gases
- Scientists have long recognized that gases dissolved in magma provide the driving force of volcanic eruptions, but only recently have new techniques permitted routine measurement of different types of volcanic gases released into the atmosphere. Sulfurous volcanic gas and visible steam are usually the first things people notice when they visit an active volcano, for example Mount St. Helens pictured here. A number of other gases also escape sight unseen into the atmosphere through hot fumaroles, active vents, and porous ground surfaces. The gases escape as magma rises toward the surface, when it erupts, and even as it cools and crystallizes below ground.
- A primary objective in gas monitoring is to determine changes in the release of certain gases from a volcano, chiefly carbon dioxide and sulfur dioxide. Such changes can be used with other monitoring information to provide eruption warnings and to improve our understanding of how volcanoes work. In recent years, we have directed increased attention toward volcanic gas emissions because of the newly appreciated hazards they sometimes pose and their effects on the Earth's atmosphere and climate.
- Gases released by most volcanoes are difficult to sample and measure on a regular basis, especially when a volcano becomes restless. Direct sampling of gas requires that scientists visit a hot fumarole or an active vent, usually high on a volcano's flank or within its summit crater. At some volcanoes, gases discharge directly into crater lakes. The remote location of these sampling sites, intense and often hazardous fumes, frequent bad weather, and the potential for sudden eruptions can make regular gas sampling sometimes impossible and dangerous.
- Measuring gases remotely is possible but requires ideal weather and the availability of suitable aircraft or a network of roads around a volcano. Consistent and favorable wind conditions are needed to carry gases from vents and fissures to where they can be measured. In some cases, automated on-site gas monitoring is feasible. Under corrosive conditions, only a few sensors are available, however, for continuously recording the concentrations of specific gases.
- Scientists face yet another challenge--acid gases, like SO2, easily dissolve in water. Thus, volcanoes with abundant surface or subsurface water can prevent scientists from measuring the emission of acid gases as magma rises toward the surface and even after explosive eruptions. Because CO2 is is less likely to be masked by the presence of water, measuring it when a volcano first becomes restless and between eruptions may be important for determining whether significant magma degassing is occurring.
Which choice provides the best evidence for the answer to the previous question?
Answer 1: this response is correct because the paragraph in question details the positive effects of volcanoes (which comes right after the part about their destructive qualities).
A Short Essay on Volcanoes
- A volcano is an opening, in the planet’s surface which allows hot, molten rock, ash and gases to escape from below the surface.
- The name, “volcano” originates from the name Vulcan, a god of fire in Roman mythology. Volcanoes are like giant safety valves that release the pressure that builds up inside the Earth. The Hawaii islands were formed by 5 volcanoes. Classified by the extent of their activity volcanoes are of four types. An ‘active’ volcano is one that erupts regularly. There are about 500 known active volcanoes on Earth, not counting those that lie beneath the sea.
- A ‘dormant’ volcano is one that has not erupted for many years, although there is still some activity deep inside it. An ‘extinct’ volcano is one which has ceased to be active.
- A volcanic eruption occurs when hot rocks and lava burst from a volcano; and geysers and springs are actually just volcanoes that throw boiling water high in the air. They are caused by volcanic heat warming trapped ground water. The liquid rocks inside a volcano are called magma and when it flows out it is called as lava.
- Fresh lava has temperatures from 700 degrees C to 1200’C and glows red-hot to white hot as it flows. The most dangerous volcanic eruption recorded is the eruption of Mount St. Helens in Washington. The tallest volcano in the world is the Ojos del Salado, a volcano in Chile. The world’s largest volcano is the Muano Loa in Hawaii.
- Volcanoes are generally concentrated on the edge of continents, along the island chain, or beneath the sea forming long mountain ranges. A major part of the world’s active volcanoes above sea level encircle the Pacific Ocean forming the “Ring of Fire.”
- Volcanoes can have serious affects on the lands and people around them when they erupt. The destruction they leave in their wake accounts for the total annihilation of the surrounding landscape. Around 2, 00,000 people have lost their lives to volcanic eruptions in the past five hundred years.
- Buildings are destroyed, people are rendered homeless, people are killed, plant and animal life are both destroyed and the poisonous gases that emanate from the volcanoes can cause death and diseases like pneumonia in the people who survive it.
- However not everything associated with the volcanoes is negative. The crust of the earth exists due to?the large volumes of magma that did not erupt but instead cooled below the surface. It results in rich soil which is good for cultivation.
- The volcanic ash that blows out of the volcano increases soil fertility by adding nutrients to the soil. Ground water heated by magma can be tapped for geothermal energy. Most of the metallic minerals like copper, gold, silver, lead and zinc are mined from the magmas found deep within the roots of extinct volcanoes.
- With the increasing studies done by scientists on volcanoes it is becoming possible to gauge the activity level of a volcano. With this information although it might not be possible to prevent the erupting of a volcano at least the massive destruction of lives can be avoided by getting people evacuated in time.
Monitoring Volcanic Gases
- Scientists have long recognized that gases dissolved in magma provide the driving force of volcanic eruptions, but only recently have new techniques permitted routine measurement of different types of volcanic gases released into the atmosphere. Sulfurous volcanic gas and visible steam are usually the first things people notice when they visit an active volcano, for example Mount St. Helens pictured here. A number of other gases also escape sight unseen into the atmosphere through hot fumaroles, active vents, and porous ground surfaces. The gases escape as magma rises toward the surface, when it erupts, and even as it cools and crystallizes below ground.
- A primary objective in gas monitoring is to determine changes in the release of certain gases from a volcano, chiefly carbon dioxide and sulfur dioxide. Such changes can be used with other monitoring information to provide eruption warnings and to improve our understanding of how volcanoes work. In recent years, we have directed increased attention toward volcanic gas emissions because of the newly appreciated hazards they sometimes pose and their effects on the Earth's atmosphere and climate.
- Gases released by most volcanoes are difficult to sample and measure on a regular basis, especially when a volcano becomes restless. Direct sampling of gas requires that scientists visit a hot fumarole or an active vent, usually high on a volcano's flank or within its summit crater. At some volcanoes, gases discharge directly into crater lakes. The remote location of these sampling sites, intense and often hazardous fumes, frequent bad weather, and the potential for sudden eruptions can make regular gas sampling sometimes impossible and dangerous.
- Measuring gases remotely is possible but requires ideal weather and the availability of suitable aircraft or a network of roads around a volcano. Consistent and favorable wind conditions are needed to carry gases from vents and fissures to where they can be measured. In some cases, automated on-site gas monitoring is feasible. Under corrosive conditions, only a few sensors are available, however, for continuously recording the concentrations of specific gases.
- Scientists face yet another challenge--acid gases, like SO2, easily dissolve in water. Thus, volcanoes with abundant surface or subsurface water can prevent scientists from measuring the emission of acid gases as magma rises toward the surface and even after explosive eruptions. Because CO2 is is less likely to be masked by the presence of water, measuring it when a volcano first becomes restless and between eruptions may be important for determining whether significant magma degassing is occurring.
The author of passage 1 mentions "Vulcan," the god of Roman mythology, primarily to
Answer 1: this is the only choice that makes sense when grouped with the four options.
A Short Essay on Volcanoes
- A volcano is an opening, in the planet’s surface which allows hot, molten rock, ash and gases to escape from below the surface.
- The name, “volcano” originates from the name Vulcan, a god of fire in Roman mythology. Volcanoes are like giant safety valves that release the pressure that builds up inside the Earth. The Hawaii islands were formed by 5 volcanoes. Classified by the extent of their activity volcanoes are of four types. An ‘active’ volcano is one that erupts regularly. There are about 500 known active volcanoes on Earth, not counting those that lie beneath the sea.
- A ‘dormant’ volcano is one that has not erupted for many years, although there is still some activity deep inside it. An ‘extinct’ volcano is one which has ceased to be active.
- A volcanic eruption occurs when hot rocks and lava burst from a volcano; and geysers and springs are actually just volcanoes that throw boiling water high in the air. They are caused by volcanic heat warming trapped ground water. The liquid rocks inside a volcano are called magma and when it flows out it is called as lava.
- Fresh lava has temperatures from 700 degrees C to 1200’C and glows red-hot to white hot as it flows. The most dangerous volcanic eruption recorded is the eruption of Mount St. Helens in Washington. The tallest volcano in the world is the Ojos del Salado, a volcano in Chile. The world’s largest volcano is the Muano Loa in Hawaii.
- Volcanoes are generally concentrated on the edge of continents, along the island chain, or beneath the sea forming long mountain ranges. A major part of the world’s active volcanoes above sea level encircle the Pacific Ocean forming the “Ring of Fire.”
- Volcanoes can have serious affects on the lands and people around them when they erupt. The destruction they leave in their wake accounts for the total annihilation of the surrounding landscape. Around 2, 00,000 people have lost their lives to volcanic eruptions in the past five hundred years.
- Buildings are destroyed, people are rendered homeless, people are killed, plant and animal life are both destroyed and the poisonous gases that emanate from the volcanoes can cause death and diseases like pneumonia in the people who survive it.
- However not everything associated with the volcanoes is negative. The crust of the earth exists due to?the large volumes of magma that did not erupt but instead cooled below the surface. It results in rich soil which is good for cultivation.
- The volcanic ash that blows out of the volcano increases soil fertility by adding nutrients to the soil. Ground water heated by magma can be tapped for geothermal energy. Most of the metallic minerals like copper, gold, silver, lead and zinc are mined from the magmas found deep within the roots of extinct volcanoes.
- With the increasing studies done by scientists on volcanoes it is becoming possible to gauge the activity level of a volcano. With this information although it might not be possible to prevent the erupting of a volcano at least the massive destruction of lives can be avoided by getting people evacuated in time.
Monitoring Volcanic Gases
- Scientists have long recognized that gases dissolved in magma provide the driving force of volcanic eruptions, but only recently have new techniques permitted routine measurement of different types of volcanic gases released into the atmosphere. Sulfurous volcanic gas and visible steam are usually the first things people notice when they visit an active volcano, for example Mount St. Helens pictured here. A number of other gases also escape sight unseen into the atmosphere through hot fumaroles, active vents, and porous ground surfaces. The gases escape as magma rises toward the surface, when it erupts, and even as it cools and crystallizes below ground.
- A primary objective in gas monitoring is to determine changes in the release of certain gases from a volcano, chiefly carbon dioxide and sulfur dioxide. Such changes can be used with other monitoring information to provide eruption warnings and to improve our understanding of how volcanoes work. In recent years, we have directed increased attention toward volcanic gas emissions because of the newly appreciated hazards they sometimes pose and their effects on the Earth's atmosphere and climate.
- Gases released by most volcanoes are difficult to sample and measure on a regular basis, especially when a volcano becomes restless. Direct sampling of gas requires that scientists visit a hot fumarole or an active vent, usually high on a volcano's flank or within its summit crater. At some volcanoes, gases discharge directly into crater lakes. The remote location of these sampling sites, intense and often hazardous fumes, frequent bad weather, and the potential for sudden eruptions can make regular gas sampling sometimes impossible and dangerous.
- Measuring gases remotely is possible but requires ideal weather and the availability of suitable aircraft or a network of roads around a volcano. Consistent and favorable wind conditions are needed to carry gases from vents and fissures to where they can be measured. In some cases, automated on-site gas monitoring is feasible. Under corrosive conditions, only a few sensors are available, however, for continuously recording the concentrations of specific gases.
- Scientists face yet another challenge--acid gases, like SO2, easily dissolve in water. Thus, volcanoes with abundant surface or subsurface water can prevent scientists from measuring the emission of acid gases as magma rises toward the surface and even after explosive eruptions. Because CO2 is is less likely to be masked by the presence of water, measuring it when a volcano first becomes restless and between eruptions may be important for determining whether significant magma degassing is occurring.
Passage 1 suggests that active volcanoes
Answer 4: the author is only willing to give a number on the land-based volcanoes, but he does mention those located in the sea.
A Short Essay on Volcanoes
- A volcano is an opening, in the planet’s surface which allows hot, molten rock, ash and gases to escape from below the surface.
- The name, “volcano” originates from the name Vulcan, a god of fire in Roman mythology. Volcanoes are like giant safety valves that release the pressure that builds up inside the Earth. The Hawaii islands were formed by 5 volcanoes. Classified by the extent of their activity volcanoes are of four types. An ‘active’ volcano is one that erupts regularly. There are about 500 known active volcanoes on Earth, not counting those that lie beneath the sea.
- A ‘dormant’ volcano is one that has not erupted for many years, although there is still some activity deep inside it. An ‘extinct’ volcano is one which has ceased to be active.
- A volcanic eruption occurs when hot rocks and lava burst from a volcano; and geysers and springs are actually just volcanoes that throw boiling water high in the air. They are caused by volcanic heat warming trapped ground water. The liquid rocks inside a volcano are called magma and when it flows out it is called as lava.
- Fresh lava has temperatures from 700 degrees C to 1200’C and glows red-hot to white hot as it flows. The most dangerous volcanic eruption recorded is the eruption of Mount St. Helens in Washington. The tallest volcano in the world is the Ojos del Salado, a volcano in Chile. The world’s largest volcano is the Muano Loa in Hawaii.
- Volcanoes are generally concentrated on the edge of continents, along the island chain, or beneath the sea forming long mountain ranges. A major part of the world’s active volcanoes above sea level encircle the Pacific Ocean forming the “Ring of Fire.”
- Volcanoes can have serious affects on the lands and people around them when they erupt. The destruction they leave in their wake accounts for the total annihilation of the surrounding landscape. Around 2, 00,000 people have lost their lives to volcanic eruptions in the past five hundred years.
- Buildings are destroyed, people are rendered homeless, people are killed, plant and animal life are both destroyed and the poisonous gases that emanate from the volcanoes can cause death and diseases like pneumonia in the people who survive it.
- However not everything associated with the volcanoes is negative. The crust of the earth exists due to?the large volumes of magma that did not erupt but instead cooled below the surface. It results in rich soil which is good for cultivation.
- The volcanic ash that blows out of the volcano increases soil fertility by adding nutrients to the soil. Ground water heated by magma can be tapped for geothermal energy. Most of the metallic minerals like copper, gold, silver, lead and zinc are mined from the magmas found deep within the roots of extinct volcanoes.
- With the increasing studies done by scientists on volcanoes it is becoming possible to gauge the activity level of a volcano. With this information although it might not be possible to prevent the erupting of a volcano at least the massive destruction of lives can be avoided by getting people evacuated in time.
Monitoring Volcanic Gases
- Scientists have long recognized that gases dissolved in magma provide the driving force of volcanic eruptions, but only recently have new techniques permitted routine measurement of different types of volcanic gases released into the atmosphere. Sulfurous volcanic gas and visible steam are usually the first things people notice when they visit an active volcano, for example Mount St. Helens pictured here. A number of other gases also escape sight unseen into the atmosphere through hot fumaroles, active vents, and porous ground surfaces. The gases escape as magma rises toward the surface, when it erupts, and even as it cools and crystallizes below ground.
- A primary objective in gas monitoring is to determine changes in the release of certain gases from a volcano, chiefly carbon dioxide and sulfur dioxide. Such changes can be used with other monitoring information to provide eruption warnings and to improve our understanding of how volcanoes work. In recent years, we have directed increased attention toward volcanic gas emissions because of the newly appreciated hazards they sometimes pose and their effects on the Earth's atmosphere and climate.
- Gases released by most volcanoes are difficult to sample and measure on a regular basis, especially when a volcano becomes restless. Direct sampling of gas requires that scientists visit a hot fumarole or an active vent, usually high on a volcano's flank or within its summit crater. At some volcanoes, gases discharge directly into crater lakes. The remote location of these sampling sites, intense and often hazardous fumes, frequent bad weather, and the potential for sudden eruptions can make regular gas sampling sometimes impossible and dangerous.
- Measuring gases remotely is possible but requires ideal weather and the availability of suitable aircraft or a network of roads around a volcano. Consistent and favorable wind conditions are needed to carry gases from vents and fissures to where they can be measured. In some cases, automated on-site gas monitoring is feasible. Under corrosive conditions, only a few sensors are available, however, for continuously recording the concentrations of specific gases.
- Scientists face yet another challenge--acid gases, like SO2, easily dissolve in water. Thus, volcanoes with abundant surface or subsurface water can prevent scientists from measuring the emission of acid gases as magma rises toward the surface and even after explosive eruptions. Because CO2 is is less likely to be masked by the presence of water, measuring it when a volcano first becomes restless and between eruptions may be important for determining whether significant magma degassing is occurring.
As used in the first passage in paragraph 6, "concentrated" means
Answer 3: simply plug in the other options, and they do not make sense in the context.