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Directions: After reading the passage, read and respond to the questions that follow by selecting the best choice for each one.
[1] An atmospheric gas that absorbs and emits thermal radiation in the infrared range is known as a greenhouse gas. [2] Without such gases, the surface temperature of the earth would have been a frigid -18°C instead of the current 15°C. [3] Many climate scientists claim that human activities since the beginning of the Industrial Revolution have led to a steady increase in the atmospheric concentration of many greenhouse gases, with a consequent increase in the planet's surface temperature by about 0.85°C in the last 130 years. [4] However, in order to correctly estimate the anthropogenic changes in earth's surface temperature, it is important to quantify the effect of external natural factors like large volcanic eruptions on the planet's surface temperature.
[5] Though volcanic eruptions emit carbon dioxide, a greenhouse gas, the atmospheric concentration of this gas is about 16000 times the amount released by volcanic eruptions; therefore, no matter how large a volcanic eruption is, it cannot produce a significant change in the atmospheric carbon dioxide levels. [6] Further, the total amount of carbon dioxide emitted per year by volcanic eruptions – between 130 and 230 million tons – is roughly equivalent to that emitted in only three to five days of human activity.
[7] It is mainly through the emission of sulfur dioxide gas and ash particles into the atmosphere that large volcanic eruptions affect earth's surface temperature. [8] Sulfur dioxide reacts with the water vapor present in air to form fine particles called sulfate aerosols. [9] Winds spread the cloud of aerosols and ash particles around the globe in weeks. [10] These particles absorb incoming solar radiation and scatter it back into space, thereby producing a cooling effect on the earth. [11] They take several years to settle out of the atmosphere and thus impact the global surface temperature for many years. [12] Robock and Mao have shown that for two years after a great volcanic eruption, the surface temperature decreases by 0.1 – 0.2°C. [13] The 1991 Pinatubo eruption in Indonesia was one of the largest volcanic eruptions in the twentieth century and resulted in a global surface cooling of 0.5°C for about two to four years after the eruption.
[14] The El Chichón eruption in 1982 was the first major eruption whose climatic impact was studied in detail by modern instruments. [15] Though the emission volume of this eruption was similar to the Mount St. Helens eruption in 1980, El Chichón released seven times the amount of sulfate aerosols released by Mount St. Helens and lowered the earth's temperature by about 0.4°C as against a decrease of only 0.1°C for Mount St. Helens.
Q. It can be inferred that the highlighted word in the first paragraph is closest in meaning to
  • a)
    Created over time
  • b)
    Resulting from nature
  • c)
    Produced by humans
  • d)
    Generated in the atmosphere
  • e)
    Industrially manufactured
Correct answer is option 'C'. Can you explain this answer?
Most Upvoted Answer
Directions: After reading the passage, read and respond to the questi...
The sentence that contains the word "anthropogenic" can be simplified as: 'However, in order to correctly estimate X-type changes, we need to quantify Y-type changes.'
The phrase 'X-type' stands in for the word "anthropogenic" and 'Y-type' for "resulting from external natural factors."
From this sentence, we only get the clue that X-type is distinct from Y-type. Therefore, the word "anthropogenic" does not mean "resulting from external natural factors."
For further clue, let us look at the preceding sentence. This sentence may be simplified as:
'Some people claim that human activities…have led to [this much increase in earth's surface temperature]'
So, the type of change that is mentioned in this sentence is that which has been brought about by human activities.
Therefore, the word "anthropogenic" most likely means 'brought about by human activities.'
Let us analyze the options one by one.
  1. This option is incorrect.
  2. This option is incorrect. As discussed above, "anthropogenic" is in fact distinct from 'that which results from external natural factors' (and no mention of any other kind of natural factors is made in the passage).
  3. This option is correct and in line with the discussion above.
  4. This option is incorrect.
  5. This option is incorrect.
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Directions: After reading the passage, read and respond to the questions that follow by selecting the best choice for each one.[1] An atmospheric gas that absorbs and emits thermal radiation in the infrared range is known as a greenhouse gas. [2] Without such gases, the surface temperature of the earth would have been a frigid -18°C instead of the current 15°C. [3] Many climate scientists claim that human activities since the beginning of the Industrial Revolution have led to a steady increase in the atmospheric concentration of many greenhouse gases, with a consequent increase in the planet's surface temperature by about 0.85°C in the last 130 years. [4] However, in order to correctly estimate the anthropogenic changes in earth's surface temperature, it is important to quantify the effect of external natural factors like large volcanic eruptions on the planet's surface temperature.[5] Though volcanic eruptions emit carbon dioxide, a greenhouse gas, the atmospheric concentration of this gas is about 16000 times the amount released by volcanic eruptions; therefore, no matter how large a volcanic eruption is, it cannot produce a significant change in the atmospheric carbon dioxide levels. [6] Further, the total amount of carbon dioxide emitted per year by volcanic eruptions – between 130 and 230 million tons – is roughly equivalent to that emitted in only three to five days of human activity.[7] It is mainly through the emission of sulfur dioxide gas and ash particles into the atmosphere that large volcanic eruptions affect earth's surface temperature. [8] Sulfur dioxide reacts with the water vapor present in air to form fine particles called sulfate aerosols. [9] Winds spread the cloud of aerosols and ash particles around the globe in weeks. [10] These particles absorb incoming solar radiation and scatter it back into space, thereby producing a cooling effect on the earth. [11] They take several years to settle out of the atmosphere and thus impact the global surface temperature for many years. [12] Robock and Mao have shown that for two years after a great volcanic eruption, the surface temperature decreases by 0.1 – 0.2°C. [13] The 1991 Pinatubo eruption in Indonesia was one of the largest volcanic eruptions in the twentieth century and resulted in a global surface cooling of 0.5°C for about two to four years after the eruption.[14] The El Chichón eruption in 1982 was the first major eruption whose climatic impact was studied in detail by modern instruments. [15] Though the emission volume of this eruption was similar to the Mount St. Helens eruption in 1980, El Chichón released seven times the amount of sulfate aerosols released by Mount St. Helens and lowered the earth's temperature by about 0.4°C as against a decrease of only 0.1°C for Mount St. Helens.Q. It can be inferred that the highlighted word in the first paragraph is closest in meaning toa)Created over timeb)Resulting from naturec)Produced by humansd)Generated in the atmospheree)Industrially manufacturedCorrect answer is option 'C'. Can you explain this answer?
Question Description
Directions: After reading the passage, read and respond to the questions that follow by selecting the best choice for each one.[1] An atmospheric gas that absorbs and emits thermal radiation in the infrared range is known as a greenhouse gas. [2] Without such gases, the surface temperature of the earth would have been a frigid -18°C instead of the current 15°C. [3] Many climate scientists claim that human activities since the beginning of the Industrial Revolution have led to a steady increase in the atmospheric concentration of many greenhouse gases, with a consequent increase in the planet's surface temperature by about 0.85°C in the last 130 years. [4] However, in order to correctly estimate the anthropogenic changes in earth's surface temperature, it is important to quantify the effect of external natural factors like large volcanic eruptions on the planet's surface temperature.[5] Though volcanic eruptions emit carbon dioxide, a greenhouse gas, the atmospheric concentration of this gas is about 16000 times the amount released by volcanic eruptions; therefore, no matter how large a volcanic eruption is, it cannot produce a significant change in the atmospheric carbon dioxide levels. [6] Further, the total amount of carbon dioxide emitted per year by volcanic eruptions – between 130 and 230 million tons – is roughly equivalent to that emitted in only three to five days of human activity.[7] It is mainly through the emission of sulfur dioxide gas and ash particles into the atmosphere that large volcanic eruptions affect earth's surface temperature. [8] Sulfur dioxide reacts with the water vapor present in air to form fine particles called sulfate aerosols. [9] Winds spread the cloud of aerosols and ash particles around the globe in weeks. [10] These particles absorb incoming solar radiation and scatter it back into space, thereby producing a cooling effect on the earth. [11] They take several years to settle out of the atmosphere and thus impact the global surface temperature for many years. [12] Robock and Mao have shown that for two years after a great volcanic eruption, the surface temperature decreases by 0.1 – 0.2°C. [13] The 1991 Pinatubo eruption in Indonesia was one of the largest volcanic eruptions in the twentieth century and resulted in a global surface cooling of 0.5°C for about two to four years after the eruption.[14] The El Chichón eruption in 1982 was the first major eruption whose climatic impact was studied in detail by modern instruments. [15] Though the emission volume of this eruption was similar to the Mount St. Helens eruption in 1980, El Chichón released seven times the amount of sulfate aerosols released by Mount St. Helens and lowered the earth's temperature by about 0.4°C as against a decrease of only 0.1°C for Mount St. Helens.Q. It can be inferred that the highlighted word in the first paragraph is closest in meaning toa)Created over timeb)Resulting from naturec)Produced by humansd)Generated in the atmospheree)Industrially manufacturedCorrect answer is option 'C'. Can you explain this answer? for GRE 2024 is part of GRE preparation. The Question and answers have been prepared according to the GRE exam syllabus. Information about Directions: After reading the passage, read and respond to the questions that follow by selecting the best choice for each one.[1] An atmospheric gas that absorbs and emits thermal radiation in the infrared range is known as a greenhouse gas. [2] Without such gases, the surface temperature of the earth would have been a frigid -18°C instead of the current 15°C. [3] Many climate scientists claim that human activities since the beginning of the Industrial Revolution have led to a steady increase in the atmospheric concentration of many greenhouse gases, with a consequent increase in the planet's surface temperature by about 0.85°C in the last 130 years. [4] However, in order to correctly estimate the anthropogenic changes in earth's surface temperature, it is important to quantify the effect of external natural factors like large volcanic eruptions on the planet's surface temperature.[5] Though volcanic eruptions emit carbon dioxide, a greenhouse gas, the atmospheric concentration of this gas is about 16000 times the amount released by volcanic eruptions; therefore, no matter how large a volcanic eruption is, it cannot produce a significant change in the atmospheric carbon dioxide levels. [6] Further, the total amount of carbon dioxide emitted per year by volcanic eruptions – between 130 and 230 million tons – is roughly equivalent to that emitted in only three to five days of human activity.[7] It is mainly through the emission of sulfur dioxide gas and ash particles into the atmosphere that large volcanic eruptions affect earth's surface temperature. [8] Sulfur dioxide reacts with the water vapor present in air to form fine particles called sulfate aerosols. [9] Winds spread the cloud of aerosols and ash particles around the globe in weeks. [10] These particles absorb incoming solar radiation and scatter it back into space, thereby producing a cooling effect on the earth. [11] They take several years to settle out of the atmosphere and thus impact the global surface temperature for many years. [12] Robock and Mao have shown that for two years after a great volcanic eruption, the surface temperature decreases by 0.1 – 0.2°C. [13] The 1991 Pinatubo eruption in Indonesia was one of the largest volcanic eruptions in the twentieth century and resulted in a global surface cooling of 0.5°C for about two to four years after the eruption.[14] The El Chichón eruption in 1982 was the first major eruption whose climatic impact was studied in detail by modern instruments. [15] Though the emission volume of this eruption was similar to the Mount St. Helens eruption in 1980, El Chichón released seven times the amount of sulfate aerosols released by Mount St. Helens and lowered the earth's temperature by about 0.4°C as against a decrease of only 0.1°C for Mount St. Helens.Q. It can be inferred that the highlighted word in the first paragraph is closest in meaning toa)Created over timeb)Resulting from naturec)Produced by humansd)Generated in the atmospheree)Industrially manufacturedCorrect answer is option 'C'. Can you explain this answer? covers all topics & solutions for GRE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Directions: After reading the passage, read and respond to the questions that follow by selecting the best choice for each one.[1] An atmospheric gas that absorbs and emits thermal radiation in the infrared range is known as a greenhouse gas. [2] Without such gases, the surface temperature of the earth would have been a frigid -18°C instead of the current 15°C. [3] Many climate scientists claim that human activities since the beginning of the Industrial Revolution have led to a steady increase in the atmospheric concentration of many greenhouse gases, with a consequent increase in the planet's surface temperature by about 0.85°C in the last 130 years. [4] However, in order to correctly estimate the anthropogenic changes in earth's surface temperature, it is important to quantify the effect of external natural factors like large volcanic eruptions on the planet's surface temperature.[5] Though volcanic eruptions emit carbon dioxide, a greenhouse gas, the atmospheric concentration of this gas is about 16000 times the amount released by volcanic eruptions; therefore, no matter how large a volcanic eruption is, it cannot produce a significant change in the atmospheric carbon dioxide levels. [6] Further, the total amount of carbon dioxide emitted per year by volcanic eruptions – between 130 and 230 million tons – is roughly equivalent to that emitted in only three to five days of human activity.[7] It is mainly through the emission of sulfur dioxide gas and ash particles into the atmosphere that large volcanic eruptions affect earth's surface temperature. [8] Sulfur dioxide reacts with the water vapor present in air to form fine particles called sulfate aerosols. [9] Winds spread the cloud of aerosols and ash particles around the globe in weeks. [10] These particles absorb incoming solar radiation and scatter it back into space, thereby producing a cooling effect on the earth. [11] They take several years to settle out of the atmosphere and thus impact the global surface temperature for many years. [12] Robock and Mao have shown that for two years after a great volcanic eruption, the surface temperature decreases by 0.1 – 0.2°C. [13] The 1991 Pinatubo eruption in Indonesia was one of the largest volcanic eruptions in the twentieth century and resulted in a global surface cooling of 0.5°C for about two to four years after the eruption.[14] The El Chichón eruption in 1982 was the first major eruption whose climatic impact was studied in detail by modern instruments. [15] Though the emission volume of this eruption was similar to the Mount St. Helens eruption in 1980, El Chichón released seven times the amount of sulfate aerosols released by Mount St. Helens and lowered the earth's temperature by about 0.4°C as against a decrease of only 0.1°C for Mount St. Helens.Q. It can be inferred that the highlighted word in the first paragraph is closest in meaning toa)Created over timeb)Resulting from naturec)Produced by humansd)Generated in the atmospheree)Industrially manufacturedCorrect answer is option 'C'. Can you explain this answer?.
Solutions for Directions: After reading the passage, read and respond to the questions that follow by selecting the best choice for each one.[1] An atmospheric gas that absorbs and emits thermal radiation in the infrared range is known as a greenhouse gas. [2] Without such gases, the surface temperature of the earth would have been a frigid -18°C instead of the current 15°C. [3] Many climate scientists claim that human activities since the beginning of the Industrial Revolution have led to a steady increase in the atmospheric concentration of many greenhouse gases, with a consequent increase in the planet's surface temperature by about 0.85°C in the last 130 years. [4] However, in order to correctly estimate the anthropogenic changes in earth's surface temperature, it is important to quantify the effect of external natural factors like large volcanic eruptions on the planet's surface temperature.[5] Though volcanic eruptions emit carbon dioxide, a greenhouse gas, the atmospheric concentration of this gas is about 16000 times the amount released by volcanic eruptions; therefore, no matter how large a volcanic eruption is, it cannot produce a significant change in the atmospheric carbon dioxide levels. [6] Further, the total amount of carbon dioxide emitted per year by volcanic eruptions – between 130 and 230 million tons – is roughly equivalent to that emitted in only three to five days of human activity.[7] It is mainly through the emission of sulfur dioxide gas and ash particles into the atmosphere that large volcanic eruptions affect earth's surface temperature. [8] Sulfur dioxide reacts with the water vapor present in air to form fine particles called sulfate aerosols. [9] Winds spread the cloud of aerosols and ash particles around the globe in weeks. [10] These particles absorb incoming solar radiation and scatter it back into space, thereby producing a cooling effect on the earth. [11] They take several years to settle out of the atmosphere and thus impact the global surface temperature for many years. [12] Robock and Mao have shown that for two years after a great volcanic eruption, the surface temperature decreases by 0.1 – 0.2°C. [13] The 1991 Pinatubo eruption in Indonesia was one of the largest volcanic eruptions in the twentieth century and resulted in a global surface cooling of 0.5°C for about two to four years after the eruption.[14] The El Chichón eruption in 1982 was the first major eruption whose climatic impact was studied in detail by modern instruments. [15] Though the emission volume of this eruption was similar to the Mount St. Helens eruption in 1980, El Chichón released seven times the amount of sulfate aerosols released by Mount St. Helens and lowered the earth's temperature by about 0.4°C as against a decrease of only 0.1°C for Mount St. Helens.Q. It can be inferred that the highlighted word in the first paragraph is closest in meaning toa)Created over timeb)Resulting from naturec)Produced by humansd)Generated in the atmospheree)Industrially manufacturedCorrect answer is option 'C'. Can you explain this answer? in English & in Hindi are available as part of our courses for GRE. Download more important topics, notes, lectures and mock test series for GRE Exam by signing up for free.
Here you can find the meaning of Directions: After reading the passage, read and respond to the questions that follow by selecting the best choice for each one.[1] An atmospheric gas that absorbs and emits thermal radiation in the infrared range is known as a greenhouse gas. [2] Without such gases, the surface temperature of the earth would have been a frigid -18°C instead of the current 15°C. [3] Many climate scientists claim that human activities since the beginning of the Industrial Revolution have led to a steady increase in the atmospheric concentration of many greenhouse gases, with a consequent increase in the planet's surface temperature by about 0.85°C in the last 130 years. [4] However, in order to correctly estimate the anthropogenic changes in earth's surface temperature, it is important to quantify the effect of external natural factors like large volcanic eruptions on the planet's surface temperature.[5] Though volcanic eruptions emit carbon dioxide, a greenhouse gas, the atmospheric concentration of this gas is about 16000 times the amount released by volcanic eruptions; therefore, no matter how large a volcanic eruption is, it cannot produce a significant change in the atmospheric carbon dioxide levels. [6] Further, the total amount of carbon dioxide emitted per year by volcanic eruptions – between 130 and 230 million tons – is roughly equivalent to that emitted in only three to five days of human activity.[7] It is mainly through the emission of sulfur dioxide gas and ash particles into the atmosphere that large volcanic eruptions affect earth's surface temperature. [8] Sulfur dioxide reacts with the water vapor present in air to form fine particles called sulfate aerosols. [9] Winds spread the cloud of aerosols and ash particles around the globe in weeks. [10] These particles absorb incoming solar radiation and scatter it back into space, thereby producing a cooling effect on the earth. [11] They take several years to settle out of the atmosphere and thus impact the global surface temperature for many years. [12] Robock and Mao have shown that for two years after a great volcanic eruption, the surface temperature decreases by 0.1 – 0.2°C. [13] The 1991 Pinatubo eruption in Indonesia was one of the largest volcanic eruptions in the twentieth century and resulted in a global surface cooling of 0.5°C for about two to four years after the eruption.[14] The El Chichón eruption in 1982 was the first major eruption whose climatic impact was studied in detail by modern instruments. [15] Though the emission volume of this eruption was similar to the Mount St. Helens eruption in 1980, El Chichón released seven times the amount of sulfate aerosols released by Mount St. Helens and lowered the earth's temperature by about 0.4°C as against a decrease of only 0.1°C for Mount St. Helens.Q. It can be inferred that the highlighted word in the first paragraph is closest in meaning toa)Created over timeb)Resulting from naturec)Produced by humansd)Generated in the atmospheree)Industrially manufacturedCorrect answer is option 'C'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of Directions: After reading the passage, read and respond to the questions that follow by selecting the best choice for each one.[1] An atmospheric gas that absorbs and emits thermal radiation in the infrared range is known as a greenhouse gas. [2] Without such gases, the surface temperature of the earth would have been a frigid -18°C instead of the current 15°C. [3] Many climate scientists claim that human activities since the beginning of the Industrial Revolution have led to a steady increase in the atmospheric concentration of many greenhouse gases, with a consequent increase in the planet's surface temperature by about 0.85°C in the last 130 years. [4] However, in order to correctly estimate the anthropogenic changes in earth's surface temperature, it is important to quantify the effect of external natural factors like large volcanic eruptions on the planet's surface temperature.[5] Though volcanic eruptions emit carbon dioxide, a greenhouse gas, the atmospheric concentration of this gas is about 16000 times the amount released by volcanic eruptions; therefore, no matter how large a volcanic eruption is, it cannot produce a significant change in the atmospheric carbon dioxide levels. [6] Further, the total amount of carbon dioxide emitted per year by volcanic eruptions – between 130 and 230 million tons – is roughly equivalent to that emitted in only three to five days of human activity.[7] It is mainly through the emission of sulfur dioxide gas and ash particles into the atmosphere that large volcanic eruptions affect earth's surface temperature. [8] Sulfur dioxide reacts with the water vapor present in air to form fine particles called sulfate aerosols. [9] Winds spread the cloud of aerosols and ash particles around the globe in weeks. [10] These particles absorb incoming solar radiation and scatter it back into space, thereby producing a cooling effect on the earth. [11] They take several years to settle out of the atmosphere and thus impact the global surface temperature for many years. [12] Robock and Mao have shown that for two years after a great volcanic eruption, the surface temperature decreases by 0.1 – 0.2°C. [13] The 1991 Pinatubo eruption in Indonesia was one of the largest volcanic eruptions in the twentieth century and resulted in a global surface cooling of 0.5°C for about two to four years after the eruption.[14] The El Chichón eruption in 1982 was the first major eruption whose climatic impact was studied in detail by modern instruments. [15] Though the emission volume of this eruption was similar to the Mount St. Helens eruption in 1980, El Chichón released seven times the amount of sulfate aerosols released by Mount St. Helens and lowered the earth's temperature by about 0.4°C as against a decrease of only 0.1°C for Mount St. Helens.Q. It can be inferred that the highlighted word in the first paragraph is closest in meaning toa)Created over timeb)Resulting from naturec)Produced by humansd)Generated in the atmospheree)Industrially manufacturedCorrect answer is option 'C'. Can you explain this answer?, a detailed solution for Directions: After reading the passage, read and respond to the questions that follow by selecting the best choice for each one.[1] An atmospheric gas that absorbs and emits thermal radiation in the infrared range is known as a greenhouse gas. [2] Without such gases, the surface temperature of the earth would have been a frigid -18°C instead of the current 15°C. [3] Many climate scientists claim that human activities since the beginning of the Industrial Revolution have led to a steady increase in the atmospheric concentration of many greenhouse gases, with a consequent increase in the planet's surface temperature by about 0.85°C in the last 130 years. [4] However, in order to correctly estimate the anthropogenic changes in earth's surface temperature, it is important to quantify the effect of external natural factors like large volcanic eruptions on the planet's surface temperature.[5] Though volcanic eruptions emit carbon dioxide, a greenhouse gas, the atmospheric concentration of this gas is about 16000 times the amount released by volcanic eruptions; therefore, no matter how large a volcanic eruption is, it cannot produce a significant change in the atmospheric carbon dioxide levels. [6] Further, the total amount of carbon dioxide emitted per year by volcanic eruptions – between 130 and 230 million tons – is roughly equivalent to that emitted in only three to five days of human activity.[7] It is mainly through the emission of sulfur dioxide gas and ash particles into the atmosphere that large volcanic eruptions affect earth's surface temperature. [8] Sulfur dioxide reacts with the water vapor present in air to form fine particles called sulfate aerosols. [9] Winds spread the cloud of aerosols and ash particles around the globe in weeks. [10] These particles absorb incoming solar radiation and scatter it back into space, thereby producing a cooling effect on the earth. [11] They take several years to settle out of the atmosphere and thus impact the global surface temperature for many years. [12] Robock and Mao have shown that for two years after a great volcanic eruption, the surface temperature decreases by 0.1 – 0.2°C. [13] The 1991 Pinatubo eruption in Indonesia was one of the largest volcanic eruptions in the twentieth century and resulted in a global surface cooling of 0.5°C for about two to four years after the eruption.[14] The El Chichón eruption in 1982 was the first major eruption whose climatic impact was studied in detail by modern instruments. [15] Though the emission volume of this eruption was similar to the Mount St. Helens eruption in 1980, El Chichón released seven times the amount of sulfate aerosols released by Mount St. Helens and lowered the earth's temperature by about 0.4°C as against a decrease of only 0.1°C for Mount St. Helens.Q. It can be inferred that the highlighted word in the first paragraph is closest in meaning toa)Created over timeb)Resulting from naturec)Produced by humansd)Generated in the atmospheree)Industrially manufacturedCorrect answer is option 'C'. Can you explain this answer? has been provided alongside types of Directions: After reading the passage, read and respond to the questions that follow by selecting the best choice for each one.[1] An atmospheric gas that absorbs and emits thermal radiation in the infrared range is known as a greenhouse gas. [2] Without such gases, the surface temperature of the earth would have been a frigid -18°C instead of the current 15°C. [3] Many climate scientists claim that human activities since the beginning of the Industrial Revolution have led to a steady increase in the atmospheric concentration of many greenhouse gases, with a consequent increase in the planet's surface temperature by about 0.85°C in the last 130 years. [4] However, in order to correctly estimate the anthropogenic changes in earth's surface temperature, it is important to quantify the effect of external natural factors like large volcanic eruptions on the planet's surface temperature.[5] Though volcanic eruptions emit carbon dioxide, a greenhouse gas, the atmospheric concentration of this gas is about 16000 times the amount released by volcanic eruptions; therefore, no matter how large a volcanic eruption is, it cannot produce a significant change in the atmospheric carbon dioxide levels. [6] Further, the total amount of carbon dioxide emitted per year by volcanic eruptions – between 130 and 230 million tons – is roughly equivalent to that emitted in only three to five days of human activity.[7] It is mainly through the emission of sulfur dioxide gas and ash particles into the atmosphere that large volcanic eruptions affect earth's surface temperature. [8] Sulfur dioxide reacts with the water vapor present in air to form fine particles called sulfate aerosols. [9] Winds spread the cloud of aerosols and ash particles around the globe in weeks. [10] These particles absorb incoming solar radiation and scatter it back into space, thereby producing a cooling effect on the earth. [11] They take several years to settle out of the atmosphere and thus impact the global surface temperature for many years. [12] Robock and Mao have shown that for two years after a great volcanic eruption, the surface temperature decreases by 0.1 – 0.2°C. [13] The 1991 Pinatubo eruption in Indonesia was one of the largest volcanic eruptions in the twentieth century and resulted in a global surface cooling of 0.5°C for about two to four years after the eruption.[14] The El Chichón eruption in 1982 was the first major eruption whose climatic impact was studied in detail by modern instruments. [15] Though the emission volume of this eruption was similar to the Mount St. Helens eruption in 1980, El Chichón released seven times the amount of sulfate aerosols released by Mount St. Helens and lowered the earth's temperature by about 0.4°C as against a decrease of only 0.1°C for Mount St. Helens.Q. It can be inferred that the highlighted word in the first paragraph is closest in meaning toa)Created over timeb)Resulting from naturec)Produced by humansd)Generated in the atmospheree)Industrially manufacturedCorrect answer is option 'C'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice Directions: After reading the passage, read and respond to the questions that follow by selecting the best choice for each one.[1] An atmospheric gas that absorbs and emits thermal radiation in the infrared range is known as a greenhouse gas. [2] Without such gases, the surface temperature of the earth would have been a frigid -18°C instead of the current 15°C. [3] Many climate scientists claim that human activities since the beginning of the Industrial Revolution have led to a steady increase in the atmospheric concentration of many greenhouse gases, with a consequent increase in the planet's surface temperature by about 0.85°C in the last 130 years. [4] However, in order to correctly estimate the anthropogenic changes in earth's surface temperature, it is important to quantify the effect of external natural factors like large volcanic eruptions on the planet's surface temperature.[5] Though volcanic eruptions emit carbon dioxide, a greenhouse gas, the atmospheric concentration of this gas is about 16000 times the amount released by volcanic eruptions; therefore, no matter how large a volcanic eruption is, it cannot produce a significant change in the atmospheric carbon dioxide levels. [6] Further, the total amount of carbon dioxide emitted per year by volcanic eruptions – between 130 and 230 million tons – is roughly equivalent to that emitted in only three to five days of human activity.[7] It is mainly through the emission of sulfur dioxide gas and ash particles into the atmosphere that large volcanic eruptions affect earth's surface temperature. [8] Sulfur dioxide reacts with the water vapor present in air to form fine particles called sulfate aerosols. [9] Winds spread the cloud of aerosols and ash particles around the globe in weeks. [10] These particles absorb incoming solar radiation and scatter it back into space, thereby producing a cooling effect on the earth. [11] They take several years to settle out of the atmosphere and thus impact the global surface temperature for many years. [12] Robock and Mao have shown that for two years after a great volcanic eruption, the surface temperature decreases by 0.1 – 0.2°C. [13] The 1991 Pinatubo eruption in Indonesia was one of the largest volcanic eruptions in the twentieth century and resulted in a global surface cooling of 0.5°C for about two to four years after the eruption.[14] The El Chichón eruption in 1982 was the first major eruption whose climatic impact was studied in detail by modern instruments. [15] Though the emission volume of this eruption was similar to the Mount St. Helens eruption in 1980, El Chichón released seven times the amount of sulfate aerosols released by Mount St. Helens and lowered the earth's temperature by about 0.4°C as against a decrease of only 0.1°C for Mount St. Helens.Q. It can be inferred that the highlighted word in the first paragraph is closest in meaning toa)Created over timeb)Resulting from naturec)Produced by humansd)Generated in the atmospheree)Industrially manufacturedCorrect answer is option 'C'. Can you explain this answer? tests, examples and also practice GRE tests.
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