An attempt to assess the results of air temperature measurements from automatic weather stations in comparison to glass thermometer measurements in the context of weather types

Abstract

Abstract In the article, an attempt was undertaken to compare the results of air temperature measurements made using automatic weather stations (AWS) to those of glass thermometers. The analysis considered the aspect of weather types. On the basis of simultaneous measurements carried out with the use of AWS and glass thermometers, the accuracy of measurements for 6 synoptic stations of IMGW-PIB was assessed. The stations represented the Lower and Opole Silesia regions. Mean differences in mean monthly and seasonal air temperature values (T) between AWS and glass results are not high. They are equal to ±0.1°C, only rarely reaching −0.2°C. In cold seasons and in particular months as well, they are negative. On an annual scale, differences hardly ever occur. No connection between mean difference for mean air temperature and weather types was found. The values of mean differences for mean monthly and seasonal maximum air temperature (Tx) are equal to ±0.1°C (except Śnieżka). The differences for T and Tx are of low significance, being within the normal range. Mean differences for mean monthly and seasonal minimum air temperature (Tn) are usually positive. In warm seasons they can reach 1.1°C. In the case of most of the stations under consideration, for positive differences for Tn, an increase in average (from +0.1°C to +0.5°C) and high (+0.5°C to +1.0°C) differences is noticed. The only exceptions are the Śnieżka and Opole stations. The differences for each category are not regular, therefore no universal corrections can be implemented.