Emission measurements of 31.6 GHz absorption by atmospheric water vapor


  • D. C. Hogg,

  • F. O. Guiraud,

  • E. R. Westwater


The absorption by water vapor in the atmosphere was accurately measured at a frequency of 31.65 GHz (wavelength 9.48 mm). The data were obtained at three locations in the United States with total pressures of about 1010, 920, and 840 mbar. The continuum absorption (as differentiated from resonant absorption) was found to vary approximately as the square of the total surface pressure; the measurements and an associated modified formula for calculating the absorption are discussed. It is observed from the measurements that an additional term representing absorption by dimers is apparently not required.