Validation of chironomid-inferred temperature reconstructions in Iceland : the potential for reconstructing quantitative changes in Holocene climate

Abstract

Subfossil chironomids in short cores from two lakes in western Iceland were analysed and a chironomidmean July air temperature transfer function applied to produce chironomid-inferred temperature reconstructions for the recent past. These reconstructions were compared with local meteorological data in order to evaluate the technique in Iceland. The chironomidinferred temperature reconstructions showed similar patterns and magnitudes of change to those recorded in the instrumental data, but the chironomid temperature reconstructions slightly underpredicted the observed temperatures. This suggests that the chironomids are able to reconstruct sequence trends of temperature change although the accuracy of the actual figures produced needs to be addressed. Subfossil chironomids in Iceland can be used to reconstruct the relatively small magnitude temperature changes of the last few hundred years, and also the larger magnitude changes experienced earlier in the Holocene.