Measurements of atmospheric water vapour using the absorption band at 7250 cm-1

Measurements of the integrated absorption of the 7250 cm^-1 (1.38 μm) band of water vapour have been made for a 0.5 km horizontal path through the atmosphere. Using published band intensities the absorption values were converted to precipitable water amounts which were found to be about 10% smaller than values determined by wet and dry hygrometry. This difference is probably caused by inaccuracies in the published line parameter values, particularly those involving high rotational energy.