Alternating cold and warm periods during the European late-Holocene

Abstract. The decadal to centennial scale climate variability of the past 4000 years consists of colder and warmer periods, potentially initiated by fast varying external forcing, or the lack thereof. These alternating cold and warm periods are most clearly visualized by the waxing and waning of glaciers in the Northern Hemisphere. However, these cold and warm periods are neither spatially nor temporally consistent, and using these defined periods to interpret local variations in climate and society could prove difficult. Here, we use two global earth system models, as well as available proxy reconstructions to examine to which extent the defined warm and cold periods of the last 4000 years before the industrial period are reflected in the climate for Northern, Southern, and Central Europe. We find that on regional scales, the relative role of internal variability appears more pronounced compared to the externally forced signal, thereby decreasing the forcing signal in local climate records. In addition, one model suggests that the climate variability for Northern Europe follows the external forcing more closely than the climate of Central and especially Southern Europe, while the other model shows rather ambiguous results. This study illustrates that periods defined by glacier advances and archaeology have to be carefully used in the interpretation of past events at a local scale, as it is likely that internal variability dominates on such scales.