Climate scientists have observed seasonal changes in atmospheric carbon dioxide concentration. In the Northern Hemisphere, they have measured the highest levels of carbon dioxide in the month of May. They have also measured the lowest levels of atmospheric carbon dioxide in the month of October. Hypothesize how photosynthesis can affect these changes. Consider the process of photosynthesis and its inputs and outputs. Explain your answer in three to five sentences. Things to keep in mind as you develop your hypothesis: In the Northern Hemisphere, leaves appear on trees in the spring and fall from trees in the autumn. Leaves are where photosynthesis occurs. How does photosynthesis effect carbon dioxide? (4 points)

Answer 1

Photosynthesis plays a crucial role in regulating atmospheric carbon dioxide levels, particularly in the Northern Hemisphere. In the spring, as leaves emerge and plants begin to photosynthesize, they absorb carbon dioxide from the atmosphere to convert it into glucose and oxygen. This increased uptake of carbon dioxide leads to a decrease in atmospheric CO2 levels, which is why the lowest levels are often observed in October, as photosynthesis is still active during the growing season. Conversely, by May, when deciduous trees are fully leafed out and photosynthetic activity is at its peak, we see the highest CO2 levels because of post-winter decay and respiration processes that release CO2 back into the atmosphere, leading to the observed seasonal fluctuations.