Long-pathlength infrared absorption measurements in the 8- to 14-{mu}m atmospheric window: Self-broadening coefficient data

Conference · Sat Apr 01 04:00:00 EST 1995

OSTI ID:83185

Kulp, T J; Shinn, J ^[1]

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1. Lawrence Livermore National Lab., CA (United States)

The accurate characterization of the latent infrared (IR) absorption in the atmospheric window regions continues to be an area of research interest for the global climate modeling community. In the window between 8 and 14 {mu}m, this absorption can be attributed primarily to water vapor. It consists of (1) weak lines originating from the edge of the water vapor pure rotational band (at low wavenumbers) and the trailing P-branch of the v{sub 2} rovibrational band (at the high-wavenumber boundary of the window); and (2) the water vapor continuum absorption. The goal of our project has been to improve our quantitative and physical understanding of both of these absorption processes. Specifically, our immediate aims are to fill gaps in the experimental radiative transfer databases pertaining to the line parameters (i.e., line intensities and broadening coefficients) and to the self- and foreign-broadened water vapor continuum. To accomplish our goals, we have made long-pathlength absorption measurements using a Fourier transform infrared spectrometer (FTIR) (for the continuum and line measurements, at low resolution) and a tunable diode laser absorption spectrometer (TDLAS) (for the line measurements, at high resolution). These measurements were made on gas samples contained in a 400-m maximum pathlength Horn Pimentel multipass cell designed and constructed for this project.

• Research Organization: USDOE Office of Energy Research, Washington, DC (United States). Environmental Sciences Div.
• OSTI ID: 83185
• Report Number(s): CONF-940277--; ON: DE95009951
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
ABSORPTION
ABSORPTION SPECTROSCOPY
CLIMATE MODELS
FOURIER TRANSFORM SPECTROMETERS
GENERAL CIRCULATION MODELS
INFRARED RADIATION
WATER VAPOR