Reconstruction of remote climate changes from borehole temperatures

Data from temperature measurements in drillholes are indicators of the temperature variations associated with past climate change. The aim of this paper is to investigate the maximum extent of ground temperature history which can be extracted from geothermal data. We discuss ground surface temperature histories reconstructed from borehole temperature measurements in twelve deep holes ( 700 to 6000 m) in the Czech Republic. The study has identified climatic episodes back to the last glaciation period. The reconstructed climatic histories exhibit features similar to those extracted from borehole temperature logs by other inversion techniques and also found by independent climate reconstruction methods. Results confirm the possibility to identify long-term climatic trends from the borehole temperature-depth profiles and to integrate it into the assemblage of traditional paleoclimatological records