ATMOSPHERIC ABSORPTION OF ELECTROMAGNETIC RADIATION IN THE FREQUENCY REGION 120 TO 132 KMC/S. PART 2

The measurements and interpretation of the absorption of electromagentic radiation by the earth's atmosphere at frequencies of 120, 125, and 132 kMc/s are described in this report. Data was taken at 5 pressures corresponding to pressure altitudes in the earth's atmosphere between 8 and 0.25 km. These measurements indicate the presence of a water vapor absorption line near 121 kMc/s with a peak intensity of 0.107 db/km gm/m to the 3rd power. The anomalous values of water vapor absorption observed by previous investigators may, therefore, be due to other unpredicted water vapor lines. Measurement techniques are described and previous measurements of water vapor attenuation are summarized.