SSC
BIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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What do records from the twentieth and twenty-first century show about the concentration of carbon dioxide in the atmosphere?
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An upward trend with no annual fluctuations
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An upward trend with annual fluctuations
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Annual fluctuations but no overall trend
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Random fluctuations and no overall trend
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Explanation:
Detailed explanation-1: -The second graph shows CO2 levels during Earth’s last three glacial cycles, as captured by air bubbles trapped in ice sheets and glaciers. Since the beginning of industrial times (in the 18th century), human activities have raised atmospheric CO2 by 50% – meaning the amount of CO2 is now 150% of its value in 1750.
Detailed explanation-2: -The concentration of carbon dioxide in Earth’s atmosphere is currently at nearly 412 parts per million (ppm) and rising. This represents a 47 percent increase since the beginning of the Industrial Age, when the concentration was near 280 ppm, and an 11 percent increase since 2000, when it was near 370 ppm.
There is 1 question to complete.