Apparatus for routine measurements of the thermal conductivity of ice cores

An apparatus is described for measuring the thermal conductivity of ice by the transient hot-wire method. Thermal conductivity, lambda, is determined by tracking the thermal pulse induced in the sample by a heating source consisting of a platinum resistor. A central segment of the same platinum heating resistor acts also as a thermal sensor. A heat pulse transferred to the ice for a period of 40 s gives a maximum temperature increment of about 7-14 degrees C. In good experimental conditions, the expected reproducibility of the measurements is within +/-3%. The accuracy of the method depends on whether the instrument has been calibrated by reliable standard samples, certified by absolute methods.