July 23, 1976
Project Location: 
North America (Colorado - Washington - Alaska - Canda)
Project Description: 

Because of the unique roll played by the hydroxide (OH) free radical in controlling tropospheric chemistry, the Global Atmospheric Measurements Experiment on Tropospheric Aerosols and Gases (GAMETAG) project collected measurements of tropospheric OH. The main objective of this experimental was to determine, for the first time, the average global steady state concentration of OH. The technique that was used in these measurements was the newly developed method of laser-induced fluorescence. Because the OH concentration is strongly influenced by a large number of other trace gases, as well as the ultraviolet (UV) flux, these other gases and the UV flux was monitored to provide as complete a description as possible of the chemical reference frame that OH is being measured in.