A need for criticality in the interpretation of human responses to past climate change: examples from the Irish archaeological record.

Climate change has been evoked to explain numerous aspects of the Irish archaeological record, including the emergence of Late Bronze age hillforts, Early Medieval ringforts and lake settlements, as well as ebbs and wanes in the construction of bog trackways and related sites. There have been few attempts to test these hypotheses rigorously, however, owing in part to the difficulties of reconciling diverse and often imprecise chronologies available for the datasets. This paper considers dendrochronological and radiocarbon dating from more than 400 sites, including hillforts, ringforts, lake settlements and trackways, and compares their frequency to a regionally-relevant, testate-amoebae derived palaeoclimate reconstruction from Northern Ireland. The results highlight considerable complexity in the relationship of archaeological and palaeoclimate "events", with changes in the archaeological records sometimes preceding, coinciding with or following palaeoclimate shifts, and sometimes occurring irrespective of any perceptible climate change. Potential explanations for these diverse relationships are explored, including the limitations of the datasets and the wider cultural significance of the archaeological site-types that are examined. We conclude that there is a need for criticality in the interpretation of past cultural change if the impact of palaeoclimate change on human populations is to be understood in a meaningful way.