Fourier Transform Infrared Spectroscopy


 

Instrument:Fourier Transform Infrared Spectroscopy
Principal Investigators:William G. Mankin and Michael T. Coffey
Co-Investigators:James W. Hannigan and Steven T. Massie
Organization:National Center for Atmospheric Research
P. O. Box 3000
Boulder, CO 80307
Co-Investigators:David Glandorf and Margaret A. Tolbert
Organization:University of Colorado

Measurement Description: The NCAR Fourier transform spectrometer will record high-resolution solar infrared absorption spectra of the atmosphere above the DC-8 aircraft. From these absorption spectra column abundances of a number of stratospheric gases important to polar ozone chemistry will be derived. The spectra also will be used to attempt to detect the infrared absorption signature of polar stratospheric clouds so that the phase and composition of those clouds can be determined. The instrument has flown successfully on the DC-8 on three polar programs since 1987. Details of the column retrieval method may be found in Mankin and Coffey, 1989; and Coffey et al., 1989. Stratospheric gases that have been retrieved during the airborne field programs are listed in Table 1.

The major chlorine reservoirs (HCl and ClONO2), the important nitrogen-containing gases in the stratosphere (N2O, NO, NO2, and HNO3), stratospheric and tropospheric tracers (HF, CH4, C2H6, H2O, CO2), a major source CFC (CF2Cl2) and ozone may be routinely retrieved.

Table 1. Molecules observed with the NCAR Fourier Transform Spectrometer
N2H2OCO2CF2Cl2HCNN2OHClO2
HDOCOCFCl3OCSNOHFO3CH6
SO2NO2C2H6HNO3ClONO2   

 

References:

Coffey, M. T., W. G. Mankin, and A. Goldman, Airborne measurements of stratospheric constituents over Antarctica in the austral spring 1987: 2. Halogen and nitrogen trace gases, J. Geophys. Res., 94, 16597-16614, 1989.
Mankin, W. G., and M. T. Coffey, Airborne measurements of stratospheric constituents over Antarctica in the austral spring 1987: 1. Method and ozone observations, J. Geophys. Res., 94, 11413-11421, 1989.