How nitrogen from farms and wildfires affects air quality

In warm weather, nitrogen compounds borne by wildfire smoke boost ozone in places like Denver. Credit: Flickr user Lee Stonehouse

Nitrogen makes up 78 percent of our atmosphere and is essential to life on Earth. Still, nitrogen pollution can impact air quality when compounds like ammonia and nitrous oxide become too abundant. Nitrogen can transform in the atmosphere through a process known as nitrogen partitioning. This process determines whether nitrogen stays in its gaseous form or turns into harmful particulate matter or ozone. Understanding this transformation is key to predicting and managing pollution. Two recent studies supported by the Climate Program Office’s Atmospheric Chemistry, Carbon Cycle and Climate (AC4) program investigated animal feeding operations and wildfires as major sources of nitrogen pollution in the U.S.