Millennial-timescale quantitative estimates of climate dynamics in central Europe from earthworm calcite granules in loess deposits

Ice core and marine archives provide detailed quantitative records of last glacial climate changes, whereas comparable terrestrial records from the mid-latitudes remain scarce. Here we quantify warm season land-surface temperatures and precipitation over millennial timescales for central Europe for the period spanning 45,000–22,000 years before present that derive from two temporally overlapping loess-palaeosol-sequences, dated at high resolution by radiocarbon on earthworm calcite granules. Interstadial temperatures were 1–4 °C warmer than stadial climate, a temperature difference which is strongly attenuated compared to Greenland records. We show that climate in the Rhine Valley was significantly cooler during the warm season and overall drier with annual precipitation values reduced by up to 70% compared to the present day. We combine quantitative estimates with mesoscale wind and moisture transport modelling demonstrating that this region was dominated by westerlies and thereby inextricably linked to North Atlantic climate forcing, although ameliorated.