An integrated method for reconstructing regional palaeoclimates: Australia (18,000 yr B.P.)

Archaeological research on human behavioural adaptations to changes in climate/environment requires palaeoclimatic reconstruction on a regional scale. Most often, neither proxy data nor numerical modelling alone can adequately meet this requirement. In an effort to satisfy this need, the author suggests a method based seasonal circulation patterns and calculations of changes in evaporation rates over land and ocean. In this paper, circulation models for Australia at 18,000 yr B.P. are based on output from NCARʹs Community Climate Model and evaporation rate changes are calculated for twelve regions within Australia, as well as eight offshore. Winter and summer palaeoclimates for each of these areas are retrodicted on the basis of these changes, and these retrodictions are tested against the available proxy data. While there are clear discrepancies between the data and retrodictions for the southern part of the continent, the method performs well in the north. This method has proven useful in reconciling apparently contradictory data, and in allowing retrodictions on the seasonal level and for providing palaeoclimatic estimates areas where data are scarce.