FORESTRY
ECOLOGY AND ENVIRONMENT
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Over the past 200 years, the level of carbon dioxide in the atmosphere has
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increased steadily.
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increased, but recently decreased.
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decreased steadily.
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shown no change.
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Explanation:
Detailed explanation-1: -Carbon dioxide concentrations have increased substantially since the beginning of the industrial era, rising from an annual average of 280 ppm in the late 1700s to 414 ppm in 2021 (average of five sites in Figure 1)-a 48 percent increase. Almost all of this increase is due to human activities.
Detailed explanation-2: -There is an overall upward trend since data collection began. Global monthly average concentrations of carbon dioxide have risen steadily from 339 parts per million in 1980 (averaged over the year) to 415 parts per million in 2021, an increase of more than 20% in 42 years.
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