An Inexpensive Thermocouple Probe-Amplifier and its Response to Rapid Temperature Fluctuations in a Mountain Forest

Abstract A sensitive, fast-response temperature probe is important for studying heat flux in the surface layer. This paper describes the construction of an amplifier for use with a fast-response thermocouple probe and presents field data collected with the probe-amplifier assembly. The thermocouple amplifier is based on an Analog Devices AD594CD monolithic thermocouple amplifier with cold junction compensation. The probe uses type E thermocouple wire of extremely small diameter and is available commercially. Laboratory calibration of the amplifier against known temperatures was linear, with a slope new theoretical expectation. The probe amplifier is easy to deploy and responds accurately to rapid temperatures fluctuations. The fine-wire junction is fragile, but inexpensive to repair.