The discovery of the near infrared windows into the Venus deep atmosphere hasenabled the use of remote sensing techniques to study the composition of theVenus atmosphere below the clouds. In particular, water vapor absorption linescan be observed in a number of the near-infrared windows allowing measurementof the H2O abundance at several different levels in the lower atmosphere.Accurate determination of the abundance requires a good database of spectralline parameters for the H2O absorption lines at the high temperatures (up to~700 K) encountered in the Venus deep atmosphere. This paper presents acomparison of a number of H2O line lists that have been, or that couldpotentially be used, to analyze Venus deep atmosphere water abundances andshows that there are substantial discrepancies between them. For example, theearly high-temperature list used by Meadows and Crisp (1996) had largesystematic errors in line intensities. When these are corrected for using themore recent high-temperature BT2 list of Barber et al. (2006) their value of45+/-10 ppm for the water vapor mixing ratio reduces to 27+/-6 ppm. The HITRANand GEISA lists used for most other studies of Venus are deficient in "hot"lines that become important in the Venus deep atmosphere and also show evidenceof systematic errors in line intensities, particularly for the 8000 to 9500cm-1 region that includes the 1.18 um window. Water vapor mixing ratios derivedfrom these lists may also be somewhat overestimated. The BT2 line list isrecommended as being the most complete and accurate current representation ofthe H2O spectrum at Venus temperatures.
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