New infrared absorption cross sections for the infrared limb sounding of carbon tetrafluoride (CF4)

Carbon tetrafluoride (CF4), also known as tetrafluoromethane and sometimes CFC-14, has a natural lithospheric source, however the enhanced modern-day concentrations relative to this source have arisen from leaks into atmosphere by industry, most significantly related production of aluminium semiconductors. A potent greenhouse gas, with one longest atmospheric lifetimes 50,000 years, abundance carbon is steadily increasing in atmosphere. In order monitor its concentration profiles using infrared sounders, accurate laboratory spectroscopic data are required. This work describes new high-resolution absorption cross sections pure air-broadened over spectral range 1190–1336 cm−1, derived spectra recorded Fourier transform spectrometer (Bruker IFS 125HR) 26-cm-pathlength cell. Spectra were at resolutions between 0.0018 0.03 cm−1 (calculated 0.9/MOPD; MOPD = maximum optical path difference) atmospherically relevant temperatures (190 – 296 K) pressures (up 760 Torr). These improve upon those previously used for remote sensing, will provide more basis retrievals future.