Question
Why does atmospheric CO2 fluctuate up-and-down, as shown in this diagram?
Atmospheric CO2
Group of answer choices
Atmospheric carbon dioxide fluctuates up-and-down because it is very difficult to make this type of measurement accurately.
Humans have changed the carbon cycle, so atmospheric carbon dioxide is now fluctuating.
Carbon dioxide in the atmosphere varies seasonally because of variations in photosynthetic activity between summer and winter.
Scientists don't really know why this is.
None of the above answers is correct.
Atmospheric CO2
Group of answer choices
Atmospheric carbon dioxide fluctuates up-and-down because it is very difficult to make this type of measurement accurately.
Humans have changed the carbon cycle, so atmospheric carbon dioxide is now fluctuating.
Carbon dioxide in the atmosphere varies seasonally because of variations in photosynthetic activity between summer and winter.
Scientists don't really know why this is.
None of the above answers is correct.
Answers
GPT-4o mini
The correct answer is:
**Carbon dioxide in the atmosphere varies seasonally because of variations in photosynthetic activity between summer and winter.**
This fluctuation is primarily due to the seasonal cycle of photosynthesis in plants. During the growing season (spring and summer), plants absorb significant amounts of CO2 as they photosynthesize, leading to a decrease in atmospheric CO2 levels. Conversely, during the fall and winter, when many plants are dormant or have shed their leaves, photosynthesis declines, and CO2 levels tend to rise again. This cyclical pattern contributes to the fluctuations observed in atmospheric CO2 measurements.
**Carbon dioxide in the atmosphere varies seasonally because of variations in photosynthetic activity between summer and winter.**
This fluctuation is primarily due to the seasonal cycle of photosynthesis in plants. During the growing season (spring and summer), plants absorb significant amounts of CO2 as they photosynthesize, leading to a decrease in atmospheric CO2 levels. Conversely, during the fall and winter, when many plants are dormant or have shed their leaves, photosynthesis declines, and CO2 levels tend to rise again. This cyclical pattern contributes to the fluctuations observed in atmospheric CO2 measurements.