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.

Question

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)

short and simple

Answer 1

In the Northern Hemisphere, the seasonal changes in atmospheric carbon dioxide levels can be attributed to the cycle of photosynthesis. During spring and summer, when leaves are fully developed, photosynthesis rates increase, as plants absorb carbon dioxide from the atmosphere to produce glucose and oxygen. This leads to a decrease in atmospheric carbon dioxide levels, which is often lowest in October when leaves start to fall. Conversely, by May, after several months of active photosynthesis, carbon dioxide levels are highest, as the rapid growth of plants leads to significant carbon uptake before the leaves start to die off.