Fourier Transform Infrared Spectrometry in Atmospheric and Trace Gas Analysis
Environment: Trace Gas Monitoring
Published Online: 15 SEP 2006
Copyright © 2000 John Wiley & Sons, Ltd. All rights reserved.
Encyclopedia of Analytical Chemistry
How to Cite
Griffith, D. W. and Jamie, I. M. 2006. Fourier Transform Infrared Spectrometry in Atmospheric and Trace Gas Analysis. Encyclopedia of Analytical Chemistry. .
- Published Online: 15 SEP 2006
Fourier transform infrared (FTIR) spectrometry is the dominant technique used to measure the infrared (IR) absorption and emission spectra of most materials, with substantial advantages in signal-to-noise ratio (S/N), resolution, speed and detection limits over conventional dispersive spectroscopy. In this application, FTIR spectrometry is used to measure the trace gas composition of the atmosphere. Applications to both clean and polluted air are described. Techniques include measurements over open paths in situ, sampling and measurement in closed cells in the field or laboratory and, briefly, remote sensing using the sun, sky or natural hot objects as an IR radiation source. The techniques are applicable to a very wide range of compounds, including labile or reactive species, and all species are measured simultaneously. Detection limits vary with the application but are typically of the order of parts per billion (nmol mol−1) in air.