This work investigated the spatial-temporal variability of temperature and thermal diffusivity of Lagoa Seca-PB soil. To achieve this, we used temperature sensors, programmed to operate continuously over the daily cycles, installed in four distinct depths of soil. We monitored the soil's thermal behavior throughout a one-year period from 2010 to 2011. In order to estimate the soil's thermal diffusivity, we employed three distinct methods: the amplitude method, the arctangent method and the logarithmic method. The soil's thermal regime, i.e., the hours and months of occurrence of maximum and minimum temperatures, was very similar in both years. The arctangent method was inadequate to estimate the soil's thermal diffusivity, considering the specific layer between 5 and 50 cm depth.
soil physics; soil temperature; thermal diffusivity; thermal regime