Late Holocene temperature record from southwestern Australia: evidence of global warming from deep boreholes

A ground surface temperature history for the lost 500 years was created from the inversion of geophysical temperature logs in four deep ( > 1400 m) boreholes on the Blackwood Plateau in southwestern Australia. Modelled temperature changes show close agreement with ground surface temperature histories from elsewhere in the world for this period and indicate that the Blackwood Plateau has experienced a 0.4 K increase in mean temperature between the beginning of the sixteenth century and the 1980s, with more than half of the increase having taken place after 1900, The modelling indicates that the highest temperatures in the region for the last 500 years were recorded during the twentieth century, and that the current rate of temperature change of more than 0.5 degrees K per century is higher than at any other time during this time period.