A Study of Tropospheric Refractive Index, Temperature, Humidity, and Velocity Fields Using Electromagnetic and Acoustic Wave Propagation Methods Supported by 'in situ' Measurements.

摘要

Paper 1 summarizes the potentials of different electromagnetic and acoustic wave propagation experiments as diagnostic tools in the study of the refractive-index, temperature, humidity and velocity fields in the troposphere. Papers 2 and 3 discuss measurements of horizontal wind velocity using optical line-of-sight propagation techniques. Paper 2 deals with measurements of horizontal divergence while in paper 3 the spectrum of the spatial wind together with the spectrum of air-pressure are used to deduce the propagation speed and direction of progressive gravity waves in the troposphere. Paper 4 deals with the potentials of an array of vertically pointing acoustic echo sounders to study time-dependent structures, especially waves, in the boundary layer. In paper 5 a forward scatter technique (beam-swinging) is used to deduce the vertical spectra of refractive index and air velocity. The influence of atmospheric stability on these spectra is discussed. Paper 6 discusses the spatial structure of refractive index, temperature and humidity in the lowest 2000 m of the troposphere as deduced from tethered balloon measurements.