Carbon Humidity Sensor Of GTS Radiosonde Performance Testing Results And Its Application

Relative humidity observation obtained by the radiosonde is not only very critical forunderstanding and accurately predicting atmosphere changes, but also the primary source datafor various atmosphere thermodynamic and dynamical processes studies, weather analysisand prediction, it plays a very important role in areas that verify the ground truth of satellitedata, performing radiative transfer calculations, studying air pollution models, research ofweather or climate changes and etc. GTS1 radiosonde is now widely used in China, relative humidity data can be observedby its carbon humidity sensor. Since carbon humidity sensor's resistance is significantlyinfluenced by temperature, which directly creates the error of relative humidity measurements,and causes great difference between sounding data and actual relative humidity of atmosphere,and therefore to achieve practical relative humidity data necessitate the study of the feasiblecorrection method for relative humidity sounding data. This paper have carried on a serials of tests on this kind of sensor with thetemperature-humidity control chamber, obtained testing data of its resistance changes underdifferent temperatures, based on a systematic analysis and calculation on these lab data,achieved the relative humidity correction methods, as well as established a relative humiditysurface-fitting correction equation. Having done a comparison between the data before andafter the correction, the actual correction effect indicated, the relative humidity correction datacould display the details relative humidity changes of the atmosphere during lower humidityphase that cannot show before correction, and enhanced the accuracy of the relative humiditydata. As the radiosonde has the advantage to penetrate the cloud, which can perform directexploration of the vertical cloud structure, this paper also did a initial research on the methodsof cloud determination based on the analysis of the radiosonde humidity data, studied thebasic methods and processes, designed and developed a practical cloud determination utilitysoftware, for supporting numerical analysis of the radiosonde humidity data and finding thebest cloud determination model. Using these methods, processes and the software, this studyfinally gave a suitable experimental and elementary cloud determination model based on thesystematic analysis of real radiosonde humidity data from one radiosonding station.