Air Chemistry

What is air chemistry?

Air chemistry, also called atmospheric chemistry, is a division of atmospheric science that studies the composition of chemical species that make up the atmosphere.

The composition and chemistry of the atmosphere require critical understanding for many reasons - most importantly, for defining the interaction between the atmosphere and all living organisms. The Earth's atmosphere has been altered by human activity, mostly from the beginning of the industrial revolution to the present day, and some of these changes are harmful to human health, agriculture, and ecosystems.

There is a number of critical environmental issues associated with a changing atmosphere, including

  • Photochemical smog
  • Global climate change
  • Toxic air pollutants
  • Acidic deposition
  • Stratospheric ozone depletion

Research Objectives

  • Collect profiles and concentration levels of chemical species, such as
    • Ozone (O3)
    • Nitrogen Oxides (NOx)
    • Carbon Oxide (COx)
    • Methane (CH4)
    • Water Vapor (H2O)
  • Understand chemical reactions that occur in the atmosphere
  • Understand human effects on the atmosphere in which we live

Why do we make measurements of air chemistry?


The chemicals that now make up our atmosphere can have harmful effects on both human health and ecosystems. The more we understand about the gases and aerosols that are in the atmosphere, where they are, where they are coming from and their concentrations, the better we can plan for the future health of all living organisms and the Earth on which we live.

Studies of the chemical composition of the Earth's atmosphere seek to understand the causes of these problems and, by obtaining a theoretical understanding of them, allow possible solutions to be tested and evaluate the effects of changes in government policy.

Recent EOL field projects studying atmospheric chemistry:

  • WE-CAN 2018: The Western Wildfire Experiment for Cloud Chemistry, Aerosol Absorption and Nitrogen (WE-CAN) project aims to better understand the chemistry of wildfire smoke.
  • ORCAS 2016: The O2/N2 Ratio and CO2 Airborne Southern Ocean (ORCAS) project will advance our understanding of the physical and biological controls on air-sea exchange of O2 and CO2 in the Southern Ocean. 
  • WINTER 2015: The Wintertime Investigation of Transport, Emissions, and Reactivity (WINTER) project is an atmospheric chemistry project studying the emissions and fate of pollutants during winter across the eastern U.S.

Do you still have questions about air chemistry?

If you still have a few more questions about atmospheric chemistry, feel free to ask a scientist! You can find a scientist who specializes in your particular question. Click on his or her name to send the scientist an email, or click on some of the other provided links to learn more about his or her specialty!