Recent developments in Holocene climate modelling

To improve our understanding of climate variability on decadal to centennial time-scales, it is crucial to use a hierarchy of climate models in addition to palaeoclimate reconstructions based on proxy data. Climate models give a physically consistent overview of the global climate on all time-scales. They are useful tools in palaeoclimatology, since: (i) they can be used to test hypotheses that have been inferred from palaeo-data; and (ii) they can provide plausible explanations of observed phenomena (e.g., Isarin and Renssen (1999), Kohfeld and Harrison (2000)). In recent years, considerable progress in palaeoclimate modelling has been made with the extensive use of models that consider the coupling of the different components of the climate system (atmosphere, ocean, sea-ice, vegetation). The aim of this paper is to inform the palaeo-data community on recent developments in palaeoclimate modelling, with special reference to the Holocene climate. In the first section, different model types and experiments are discussed, together with a short overview of Holocene climate modelling studies and differences between models and palaeo-data. In the second section, three important issues are further illustrated by discussing in detail three studies that use state-of-the-art models.