Physics Student Research

Document Type


Journal/Book Title/Conference

ASR Science Team Meeting

Publication Date



The temperature calibration of the Gill Instruments WindMaster Pro sonic anemometer used in the ARM SGP ECOR systems is actually a curve, but is approximated with a linear fit for field use. The original calibrations were performed in a temperature-controlled chamber. The linear fit slope is only applied to the calculation of sensible heat flux and not to the reported temperature. The linear fit results in an underestimate of sensible heat flux during cold ambient temperatures and an overestimate during hot ambient temperatures. In situ calibrations performed using five years of ARM SGP data reveal how poorly the temperature is measured by the ECOR using the linear fit approximation during cold and hot temperatures. Linear and non-linear in situ calibrations were determined for each sonic anemometer at each extended facility. In several cases, the linear calibration slopes presently being used in the ECOR configuration files need to be changed. The non-linear slopes will be used in the ECOR VAP to convert the measured temperature to ambient temperature.


Poster was presented at the ASR Science Team Meeting in San Antonio, Texas on March 2011.