(Russian Original Vol. 58, No. 4, April, 2015)

This work is devoted to estimation of the additional absorption of millimeter and submillimeter wavelengths in water vapor arising from collisional interaction of molecules due to the induced dipole moment. Absorption is modeled on the basis of ab initio data on the magnitude of the water molecule dipole moment at high densities, and common knowledge of the water vapor absorption spectrum. Using the model developed, we obtained a simple analytical expression for the absorption coefficient as a function of temperature, pressure, and frequency. Comparison of the results with known experimental data leads to the conclusion that in the range of pressures and temperatures typical of water vapor in the Earth’s atmosphere this type of absorption is negligible compared with the absorption arising due to association or dimerization of the water vapor molecules.