Measurements, made in different laboratories, of absorption by water vapor in microwave windows are compared with models for the water vapor continuum. A reanalysis of some of these measurements leads to the conclusion that the laboratory data are best represented by a combination of Liebe's [1987] millimeter-wave propagation model (MPM) for the foreign-broadened component of the water continuum and the 1993 version of MPM for the self-broadened component. This combined model is validated by comparison with measurements of atmospheric microwave emission.
Radio Science carries original scientific contributions on all aspects of electromagnetic phenomena related to physical problems. These contributions can include propagation through and interaction of electromagnetic waves with geophysical media, biological media, plasmas, and man-made structures. Coverage includes, but is not limited to, the application of electromagnetic techniques to remote sensing of the Earth and its environment, telecommunications, signals and systems, the ionosphere, and radio astronomy. All frequencies (including optical) are considered.
Absolute absorption rates of water vapor have been measured in the atmospheric window between the rotational lines at 183 and 321–325 GHz. Measurements have been carried out for pure water vapor and mixtures with N2 at atmospheric pressure. Pressure and temperature dependences are compared with models involving different lineshapes and different types of continua.
