Soil Temperature Variations in the Red Soil at Bangalore

Abstract

The air temperature and the soil temperatures at 5cm, l5cm, and 30cm depths observed at 0720 hrs and 1420 hrs IST in the red soil at Bangalore for the years 1971 to 1974 were analysed. The soil temperature gradients between 5cm and 5cm and 15cm and 30cm depths were calculated. It is observed that the peaks in the soil temperature at different depths are similar to the peaks in the air temperature. However, the minimum values in the soil temperature do not occur in the same months as the air temperature. The soil temperature gradients are negative in the morning and positive in the afternoons. The temperature gradients are found to be uniform during the southwest monsoon. The importance of the soil temperature gradients in understanding the heat movement through the soil is discussed.