The general mission of the Halocarbons and other Atmospheric Trace Species group is to quantify the distributions and magnitudes of sources and sinks for atmospheric nitrous oxide (N2O) and halogen containing compounds. HATS utilizes numerous types of platforms, including ground-based stations, towers, ocean vessels, aircraft, and balloons, to accomplish its mission. For a detailed mission statement, consult our FAQ.

You can also read about CFCs and their substitutes in stratospheric ozone depletion.

monthly means


Projects involve measuring trace gases in the upper troposphere and stratosphere on balloons and aircraft including Unpiloted Airborne Vehicles (UAVs) to help understanding the chemistry and transport of the upper atmosphere.

In Situ Program

Hourly in situ observations at NOAA/ESRL baseline observatories, Niwot Ridge, Colorado and Summit, Greenland provide information on transport, emissions, and trends.


Custom instrumentation for measuring greenhouse gases, halocarbons, substitute halocarbons, and hydrocarbons have been built for unique platforms. Some instrumentation has been provided to other countries to monitor trace gases.


Research centers on obtaining the maximum science from weekly to monthly flasks samples collected worldwide and analyzed in our Boulder labs. These samples are used to determine current and historical trends, trace gas and OH distributions, emissions, and inventories.


The oceans play an important role as sources and sinks for atmospheric trace species. The determination of fluxes between the surface seawater and the marine air require knowledge of the saturation anomaly with air and the gas exchange rate.


Research is conducted for developing and maintaining standard gas mixtures of atmospheric gases to calibrate instrumentation on the many platforms used in our studies. Custom standards provided as tertiary calibration mixtures are available.