Technical support for the measurements of atmospheric gas constituents. Final report

This research has consisted of measurements at atmospheric temperatures of the absolute intensities, air-broadened half-widths, and pressure-induced shifts of isolated infrared spectral lines, and highly accurate spectral absorption coefficients (or cross-sections) of certain continua or pseudo-continua, of several infrared-active atmospheric trace gases. The experiments have subsequently been refined by receiving guidance from several members of the ARM Science Team as well as from other people who are active world-wide in satellite-borne, aircraft-borne, balloon-borne, and other atmospheric remote sensing campaigns. The laboratory data are obtained at low temperatures relevant to the atmosphere using cryogenically cooled absorption cells, the high-resolution({approximately} 0.0016 cm{sup {minus}1}) of a Fourier transform spectrometer and, when warranted, the ultra-high spectral resolution ({approximately} 10{sup {minus}4} cm{sup {minus}1}) of a tunable diode laser spectrometer. In the case of the absorption-coefficient (or cross-section) measurements, pressure and temperatures are selected to correspond to those of the atmospheric layers. The authors have measured spectral absorption coefficients, which are also known as absorption cross-sections, k{sub {nu}} (cm{sup {minus}1} atm{sup {minus}1}), in the 9 and 11 {micro}m bands of CFC-11 (CFCl{sub 3}) and CFC-12 (CF{sub 2}Cl{sub 2}), the 7.62, 8.97, and 12.3 {micro}m bands of HFCF-22 (CHClF{sub 2}), and the 10.6 {micro}m bands of SF{sub 6}