Soil temperature profile and its readiness for controlling buildings indoors Temperature at Erbil city – Iraqi Kurdistan Region (IKR)

Tariq H.Karim, Sirwan Ali Rasha [College of Agriculture, University of Salahaddin / Department of Architecture, University of Salahaddin]

Received : 4/8/2013, Accepted : 7/11/2013

DOI Link:



Soil temperature varies both diurnally and seasonally and can determine the temperature gradient within the collector loops of the ground source heat pump. To study spatial and temporal variations of soil temperature besides investigating the possibility of using underground soil temperature of the region for the installation of ground heat exchange systems, the current study was conducted. Soil temperature was measured at two locations in Erbil city/ IKR during the period from November, 1st, 2012 to February, 28th, 2013 with temperature sensors inserted in the ground at different depths. . It has been observed that during January and February the soil temperature offered the highest and lowest fluctuations respectively and they were closely related to ambient air temperature. The results also indicated that soil temperature increased with increasing depth up to a depth of 3.5 m in most cases and thereafter started to decrease with increasing depth. Furthermore, it was shown that the reliability of soil temperature prediction from air temperature decreased with the increase in soil depth. Positive differences at a depth of 3.5 m February ranged from 13.73 to 21.56o C during the winter season from December to. The results can be valuable in planning for preheating system during the cold seasons.

KEYWORDS: Soil Temperature, air temperature, preheating system


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