The majority of atmospheric nitrous oxide is destroyed in the
stratosphere by reaction with light and excited oxygen atoms.
The breakup of nitrous oxide molecules in this way results in
an average atmospheric lifetime of around 120 years. It is this
long lifetime which helps to make nitrous oxide such a powerful
The uptake of nitrous oxide by soils is generally regarded to
be small on a global scale. It is driven by denitrification by
soil bacteria, which convert nitrous oxide into nitrogen gas.
In most global nitrous oxide budgets soil uptake is simply included
in the total net flux of nitrous oxide from soils.