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Owing to long-term similarities with regard to orbital climate forcing (i.e., low eccentricity and a dampened influence of precession), Marine Isotope Stage (MIS) 11 represents one of the closest astronomical analogues for present and future climate. Hence, insights into the climate variability of MIS 11 can contribute to a better understanding of the climatic evolution of the present (Holocene) interglacial as it would occur without human interference. In order to elucidate the natural climate variability during MIS 11, this study examines predominantly annually laminated lake sediments of Holsteinian age from Dethlingen, northern Germany. The Holsteinian interglacial is widely accepted to be the terrestrial equivalent of MIS 11c in central Europe and can be biostratigraphically correlated with the Hoxnian, Mazovian and Praclaux interglacials on the British Isles, in Poland and in France, respectively. These correlations yield the potential to cross-check the results from individual sites on a regional scale. This study is based on a multi-proxy approach including palynological, micropaleontological, sedimentological, geochemical and time series analyses within a wellconstrained chronological framework that has been established through varve counting and regional bio-stratigraphic correlations with other annually laminated archives of Holsteinian age. In particular, the here-presented study aims at (i) fingerprinting the long-term (centennial- to millennial-scale) and short-term (sub-decadal- to decadal-scale) climate variability during the Holsteinian interglacial, (ii) deciphering the nature, tempo and trigger mechanisms of abrupt climate change under interglacial boundary conditions, and (iii) assessing its impact on terrestrial ecosystems. With regard to long-term climate variability, the vegetation succession at Dethlingen as inferred from pollen data provides insights into the mesocratic to telocratic forest phases of a glacial-interglacial cycle spanning ~11500 (± 1000) years of the 15-16-ka-long Holsteinian interglacial. The development of temperate mixed forests suggests a general prevalence of mild climatic conditions during the Holsteinian. The older parts of the interglacial are characterised by the strong presence of boreal tree taxa (e.g., Picea), whereas the younger parts of the interglacial are marked by the expansion of sub-Atlantic to Atlantic forest elements (e.g., Abies, Buxus, Ilex, Quercus) and the decline of boreal tree taxa. This vegetation succession suggests a general warming trend and decreasing seasonality over the course of the Holsteinian interglacial. Based on the maximum pollen abundances of indicator tree taxa (e.g., Buxus and Quercus), peak warmth was reached during the later stages of the interglacial; it was accompanied by high humidity. The forest succession of the Holsteinian interglacial was punctuated by abrupt and gradual changes in the abundances of temperate plant taxa. These vegetation changes indicate considerable intra-interglacial climate variability. In particular, two marked declines of temperate taxa leading to the transient development of boreal and sub-boreal forests were triggered by centennial-scale climate oscillations, here termed Older and Younger Holsteinian Oscillations (OHO and YHO). These oscillations occurred ~6000 and ~9000 years after the onset of the interglacial pioneer forestation in central Europe, respectively. To assess the impact of abrupt climate change on terrestrial ecosystems during the Holsteinian and to investigate the underlying driving mechanisms, the intervals spanning the OHO and the YHO at Dethlingen were subjected to decadal-scale palynological and sedimentological analyses. Based on these data, the OHO comprises a 90-year-long decline of temperate taxa associated with expansion of Pinus and non-arboreal pollen, and a subsequent 130-year-long recovery of temperate taxa marked by the pioneer expansion of Betula and Alnus. Owing to its highly characteristic imprint on vegetation dynamics, the OHO can be identified in pollen records from the central European lowlands north of 50º latitude, from the British Isles to Poland. A close inspection of individual pollen records from that region reveals the prevalence of colder winters during the OHO, with a gradient of decreasing temperature and moisture availability, and increased continentality towards eastern Europe. This climate pattern points to a weakened influence of the westerlies and/or stronger influence of the Siberian High connected to the OHO. The vegetation dynamics during the YHO are characterised by a decline of temperate taxa (particularly of Carpinus) and the expansion of pioneer trees (mainly Betula). In contrast to the OHO, frost-sensitive taxa (e.g., Ilex, Buxus and Hedera) continued to thrive. This suggests that mean winter temperatures remained relatively high (>0 ºC) during the YHO pointing to a decrease of summer warmth related to the climatic deterioration. The YHO, which has a duration on the order of 300 years, is centered within a long-term (~1500-year) decline and subsequent, millennial-scale recovery of temperate taxa. Because the impact of the OHO and the YHO on the vegetation at Dethlingen was markedly different, both short-term climate oscillations may have been caused by different trigger mechanisms. For the OHO, the inferred regional-scale winter cooling over central Europe lasting for several decades points to a decrease in ocean heat transport, most likely related to a transient slowdown in North Atlantic Deep Water formation. This view is supported by the strong resemblance of the OHO to the 8.2 ka event of the Holocene with regard to the duration, imprint on terrestrial ecosystems, spatial pattern of the climatic impact, timing within the respective interglacial, and prevailing interglacial boundary conditions. In contrast, the presence of frost-sensitive taxa during the YHO appears to exclude a reduction in oceanic heat transport as postulated for the OHO. Instead, the long-lasting, gradual changes in the abundances of temperate taxa suggest a connection to orbital forcing, with the triggering mechanism causing the centennial-scale vegetation setback itself remaining unclear. The characteristics of short-term climate variability were investigated based on microfacies and time series analyses of a ~3200-year-long, annually laminated window of the Dethlingen record. The annual laminations at Dethlingen comprise biogenic varves consisting of two discrete sub-layers. The light layers, which are controlled by the intensity of diatoms blooms during spring/summer, reflect changes in the productivity of the Dethlingen palaeolake. In contrast, the dark layers, which consist predominantly of amorphous organic matter and fragmented diatom frustules, represent sediment deposition during autumn/winter. Spectral analyses of the thicknesses of the light and dark layers have revealed several peaks exceeding the 95% and 99% confidence levels that are near-identical to those known from modern instrumental data and Holocene records. Decadal-scale signals at periods of 90, 25, and 10.5 years are likely associated with the 88-, 22- and 11-year solar cycles; hence, solar activity appears to have been a forcing agent in productivity changes of the Dethlingen palaeolake. Sub-decadal-scale signals at periods between 3 and 5 years and ~6 years may reflect an influence of the El Niño-Southern Oscillation (ENSO) and the North Atlantic Oscillation (NAO) on varve formation during winter.