Errors in Radio Acoustic Sounding of Temperature

Abstract

With the use of simultaneous correction for radial wind, the accuracy of radio acoustic sounding systems for the measurement of temperature has been substantially improved. The temperature accuracy can now be affected by a number of factors that have been considered negligible in previous work. This paper describes two types of errors, those due to atmospheric effects and those due to approximations in the temperature retrieval equation. The errors are examined in a set of convective boundary layer RASS and radiosonde data. In the category of atmospheric effects, two errors are computed. The first is caused by a range error due to the gradient of signal strength. This range error is newly proposed and is approximately 0.05°?0.1°C. The second is an error due to wind and turbulence of about 0.1°C. Commonly used approximations for factors in the retrieval equation contribute errors of a few tenths of a degree Celsius. A significant difference remains after these two corrections have been applied to the sample data.