5.2 Heat Capacity and Specific Heat

Soil heat capacity is a thermal property useful for characterizing the amount of heat that can be stored in soil. More specifically, it characterizes the quantity of heat that can be added to, or removed from soil per unit change in temperature. Heat capacity therefore plays an important role in determining the magnitude of annual and diurnal variations in soil temperature. The addition or removal of heat will cause a relatively large soil temperature change in soil with low heat capacity. A direct measurement of volumetric heat capacity can be obtained by measuring the maximum temperature rise a short distance from a line heat source following the release of a heat impulse. The sensor, often referred to as a dual-probe heat-pulse sensor, can be used to obtain in situ measurements of volumetric heat capacity in both laboratory and field settings.