The Global Monitoring Division (GMD) of the National Oceanic and Atmospheric Administration's Earth Science Research Laboratory (ESRL), conducts sustained observations and research related to source ... and sink strengths, trends and global distributions of atmospheric constituents that are capable of forcing change in the climate of Earth through modification of the atmospheric radiative environment, those that may cause depletion of the global ozone layer, and those that affect baseline air quality. ESRL accomplishes this mission primarily through long-term measurements of key atmospheric species at sites spanning the globe, including five fully-equipped Baseline Observatories. These key species include carbon dioxide, carbon monoxide, methane, nitrous oxide, surface and stratospheric ozone, halogenated compounds including CFC replacements, hydrocarbons, sulfur gases, aerosols, and solar and infrared radiation. The measurements are of the highest quality and accuracy possible, and document global ch! anges in key atmospheric species, which are all affected by mankind, identifying sources of interannual variability. In addition, research programs in key regions, utilizing an array of platforms including aircraft, balloons, ocean vessels and towers, complement the land-based information. ESRL's data are used to assess climate forcing, ozone depletion and baseline air quality, to develop and test diagnostic and predictive models, and to keep the public, policy makers, and scientists abreast of the current state of our chemical and radiative atmosphere.
More info at http://www.esrl.noaa.gov/gmd/