Abstract Nitrogen oxides (NOx) are important components
of ambient and indoor air pollution and are
emitted from a range of combustion sources, including
on-road mobile sources, electric power generators, and
non-road mobile sources. While anthropogenic
sources dominate, NOx is also formed by lightning
strikes and wildland fires and is also emitted by soil.
Reduced nitrogen (e.g., ammonia, NH3) is also emitted
by various sources, including fertilizer application and
animal waste decomposition. Nitrogen oxides, ozone
(O3) and fine particulate matter (PM2.5) pollution
related to atmospheric emissions of nitrogen (N) and
other pollutants can cause premature death and a
variety of serious health effects. Climate change is
expected to impact how N-related pollutants affect
human health. For example, changes in temperature
and precipitation patterns are projected to both
lengthen the O3 season and intensify high O3 episodes
in some areas. Other climate-related changes may