Evaluation of an inexpensive temperature datalogger for meteorological applications

Recent advances in electronics miniaturization have allowed the commercial development of sensor/datalogger combinations that are sufficiently inexpen sive and appear to be sufficiently accurate to deploy in measurement arrays to resolve local atmospheric structure over periods of weeks to months. As part of an extended wintertime field experiment in the Columbia Basin of s outh-central Washington, laboratory and field tests were performed on one s uch set of battery-powered temperature dataloggers (HOBO H8 Pro from Onset Computer, Bourne, Massachusetts). Five loggers were selected for laboratory calibration. These were accurate to within 0.26 degrees C over the range f rom -5 degrees to +50 degrees C with a resolution of 0.04 degrees C or bett er. Sensor time constants were 122 +/- 6 s. Sampling intervals can be varie d over a wide range, with onboard data storage of more than 21 000 data poi nts. Field experiences with a set of 15 dataloggers are also described. The loggers appear to be suitable for a variety of meteorological applications .