Dimer Absorption within Water Vapor Bands in the IR Region

Abstract

Contributions of the absorption by water dimers to the continuum absorption by water vapor within the IR region are analyzed. They are defined as the difference between experimental data and asymptotic line wing theory (ALWT) calculations. In the ALWT calculations, the line profiles are used with parameters fitted to the Burch experimental data and to the FTIR measurements in the IR water vapor windows. Calculations with the line profile which describes the Burch data in the 2000–3000 cm−1 range are in a good agreement with CRDS measurements between other IR water vapor bands. Both profiles provide close absorption values within the water vapor bands presumably due to the contribution of stable dimers.