The construction "atmosphere_moles_of_X" means the total number of moles of X in the entire atmosphere, i.e. summed over the atmospheric column and over the entire globe. The chemical formula for nitrous oxide is N2O.
The construction "atmosphere_moles_of_X" means the total number of moles of X in the entire atmosphere, i.e. summed over the atmospheric column and over the entire globe. The chemical formula for nitrous oxide is N2O.