The International Panel on Climate Change is a group of scientists from many countries who study and monitor the temperature of Earth’s atmosphere. The panel has concluded that Earth’s climate is growing steadily warmer. The reason for this global warming, they contend, is an increase of carbon dioxide in the atmosphere, resulting from the burning of fossil fuels in power plants, factories, and automobile engines. Carbon dioxide is a greenhouse gas that causes heat to build up in the atmosphere. Although there are seasonal variations in the amount of atmospheric carbon dioxide, the panel reports that overall atmospheric levels have been steadily rising since the late 1700s, when the Industrial Revolution began. The graph below shows how atmospheric carbon dioxide concentration varies over a year. How can the dip in carbon dioxide levels shown on the graph be related to the carbon cycle? (SC.912.L.18.9)
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1 point
A. Fewer trees are cut for firewood during warmer months.
B. Erosion of farmland removes carbon dioxide from the air.
C. More carbon dioxide is dissolved in lake and ocean waters during the warm summer months.
D. Increased plant growth and photosynthesis during summer months remove more carbon dioxide from the atmosphere.