Evaluation of Air Temperature Measurements in Weather Stations

Different air temperature measurement systems in the weather station networks cause different air temperature biases. An energy balance temperature sensor was used in this study for evaluating the performance of air temperature radiation shields including the Cotton Region Shelter (CRS), the Gill shield, the MMTS shield, and the ASOS shield used in the Automated Surface Observing System (ASOS) as well as a few other radiation shields. The energy balance temperature sensor model revealed that each radiation shield created its own microclimate which in turn affected each air temperature sensor reading. The normal operating temperature readings of the CRS, the Gill, the MMTS , and the ASOS shields were compared to an highly accurate reference air temperature system (R. M. Young temperature measurement). The radiation effects (including both solar radiation and infrared radiation) and ambient air speed effects on the air temperature inside each radiation shield were detected by solving energy balance temperature sensor model.