Most of the earth’s atmosphere is nitrogen and oxygen, making up 99% of the atmosphere (approximately). So the small changes in oxygen are insignificant to the total—changes in trace gases though, especially greenhouses gases, are significant at much smaller changes in concentrations.
emandbre t1_j9q8w2d wrote
Reply to eli5: Since CO2 is increasing in the atmosphere, does that mean O2 or other gases are decreasing ? by Ok_Gas_6560
Most of the earth’s atmosphere is nitrogen and oxygen, making up 99% of the atmosphere (approximately). So the small changes in oxygen are insignificant to the total—changes in trace gases though, especially greenhouses gases, are significant at much smaller changes in concentrations.