Aridity synthesis for 8 selected key regions of the global climate system during the last 60 000 years

A compilation of published literature on dust content in terrestrial and marine sediment cores was synchronized with pollen data and speleothem growth phases on the GICC05 time axis. Aridity patterns for eight key areas of the global climate system have been reconstructed for the last 60,000 years. These records have different time resolutions and different dating methods, i.e. different types of stratigraphy. Nevertheless, all regions analyzed in this study show humid conditions during early marine isotope stage 3 (MIS3) and the early Holocene or deglaciation, but not always at the same time. Such discrepancies have been interpreted as regional effects, although stratigraphic uncertainties may affect some of the proposed interpretations. In comparison, most of the MIS2 interval becomes arid in all of the northern hemisphere records, but the peak arid conditions of the Last Glacial Maximum (LGM) and Heinrich event 1 differ in duration and intensity among regions. In addition, we also compare the aridity synthesis with modelling results using a Global Climate Model (GCM). Indeed, geological archives and GCMs show agreement of aridity pattern for the Holocene or deglaciation, LGM and for the late MIS3.