GEOLOGY

Detailed explanation-1: -The yearly fluctuations in carbon dioxide are due to seasonal plant growth, while the overall rise in carbon dioxide over many years is due to a combination of fossil fuel burning, deforestation, and cement production.

Detailed explanation-2: -As plants begin to photosynthesize in the spring and summer, they consume CO2 from the at-mosphere and eventually use it as a carbon source for growth and reproduction. This causes the decrease in CO2 levels that begins every year in May. Once winter arrives, plants save en-ergy by decreasing photosynthesis.

Detailed explanation-3: -Because photosynthetic activity is the cause of seasonal CO2 swings, regions with more plants will experience larger fluctuations. Photosynthesis also occurs in the oceans, but little of this CO2 actually moves into the atmosphere, which is why only land photosynthesizers drive seasonal cycles.

Detailed explanation-4: -During the day or in spring and summer, plants take up more carbon dioxide through photosynthesis than they release through respiration [1], and so concentrations of carbon dioxide in the air decrease.

Detailed explanation-5: -Okay, so the correct answer is that global levels carbon dioxide decline over the course of the summer of the Northern Hemisphere. The ups and downs This of the carbon dioxide levels in the northern hemisphere are due to fluctuations in the ability of plants to absorb co two.