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Investigating past interglacial climatic and environmental changes can enhance our understanding of the natural rates and ranges of climate variability under interglacial boundary conditions. However, comparing past interglacial palaeoclimate records from different regions and archives is often complicated by differing and uncertain chronologies. For instance, the duration of the Last Interglacial in Europe is still controversial as southern European palaeoclimate records suggest a duration of ~16 500–18 000 years, while a length of only ~11 000 years in northern‐central Europe was previously inferred from the analysis of partly annually laminated (varved) palaeolake sediments recovered at Bispingen, northern Germany. To resolve this discrepancy, we here present sediment microfacies, geochemistry and pollen data from a new sediment core from the Bispingen palaeolake sediment succession, covering the entire Last Interglacial (Eemian) and the earliest part of the Last Glacial (Weichselian). In particular, we provide evidence that the duration of the Last Interglacial at Bispingen must have been hitherto underestimated due to the investigation of an incomplete sediment core. Using microscopic varve counting and sedimentation rate estimates for non‐varved sections on the new sediment core, we show that the Eemian in northern‐central Europe probably lasted at least ~15 000 years, about 4000 years longer than previously thought. This new duration estimate is in much better agreement with results from southern European palaeoclimate records, clarifying the enigma of a steep trans‐European vegetation gradient for several millennia at the end of the Last Interglacial. [ABSTRACT FROM AUTHOR]

Marine sediments from continental margins provide high-resolution archives of marine and continental climate, in particular near large river mouths. The Zambezi is one of the largest rivers in East Africa, discharging large amounts of fine-grained sediments onto the western margin of the Mozambique Channel. Accurate reconstructions of past variations in river discharge can be retrieved from the depositional history of riverine sediments. In this study, sedimentation patterns along the Mozambique Margin are inferred from a series of sediment cores spanning the last 20 kyr. These cores were retrieved off the Zambezi Mouth from the shelf and from various depths at the continental slope to provide detailed information on the depositional history of this region. High-resolution X-ray fluorescence and magnetic susceptibility core scanning measurements as well as grain-size distributions of the lithogenic sediment fraction, and organic matter and carbonate content analyses resolve centennial--millennial timescale variations in sediment transport and deposition along the Mozambique Margin. Largest changes in lithogenic sediment deposition coincide with the flooding of the Mozambique Shelf. Due to deglacial sea-level rise and changes in oceanic currents, fine-grained, mainly Zambezi sediments were no longer primarily deposited south of the Zambezi Mouth, but increasingly deposited onto the Mozambique Shelf, and transported northwards over the shelf before spilling over to the slope. In addition, flooding of the shelf initiated remobilization and down-slope transport of coarse-grained, winnowed sediments. The Heinrich Event 1 and Younger Dryas are clearly indicated as events of increased fine-grained sediment deposition along the Mozambique Margin, possibly linked to increased riverine runoff from the Zambezi Catchment, which is in harmony with a southward shift of the Intertropical Convergence Zone (ITCZ) and associated African rainfall belts, causing wetter conditions. This study illustrates that interpreting marine and continental climate proxy records in the vicinity of river deltas in terms of climate change requires proper consideration of sea-level and oceanic circulation induced effects on the transport and deposition patterns of fine-grained sediments at continental slopes. [ABSTRACT FROM AUTHOR]

Abstract: The abrupt transition from fluvial to marine deposition of incised-valley-fill sediments retrieved from the southeast Vietnamese shelf, accurately records the postglacial transgression after 14ka before present (BP). Valley-filling sediments consist of fluvial mud, whereas sedimentation after the transgression is characterized by shallow-marine carbonate sands. This change in sediment composition is accurately marked in high-resolution X-ray fluorescence (XRF) core scanning records. Rapid aggradation of fluvial sediments at the river mouth nearly completely filled the Mekong incised valley prior to flooding. However, accumulation rates strongly reduced in the valley after the river-mouth system flooded and stepped back. This also affected the sediment supply to deeper parts of the southeast Vietnamese shelf. Comparison of the Mekong valley-filling with the East Asian sea-level history of sub- and inter-tidal sediment records shows that the transgressive surface preserved in the incised-valley-fill records is a robust sea-level indicator. The valley was nearly completely filled with fluvial sediments between 13.0 and 9.5 kaBP when sea-level rose rather constantly with approximately 10 mm/yr, as indicated by the East Asian sea-level record. At shallower parts of the shelf, significant sediment reworking and the establishment of estuarine conditions at the final stage of infilling complicates accurate dating of the transgressive surface. Nevertheless, incised-valley-fill records and land-based drill sites indicate a vast and rapid flooding of the shelf from the location of the modern Vietnamese coastline to the Cambodian lowlands between 9.5 ka and 8.5 kaBP. Fast flooding of this part of the shelf is related with the low shelf gradient and a strong acceleration of the East Asian sea-level rise from 34 to 9 meter below modern sea level (mbsl) corresponding to the sea-level jump of melt water pulse (MWP) 1C. [Copyright &y& Elsevier]

Highlights: [•] Degradation of IPL GDGTs in a reoxidized sediment was dependent on head group. [•] TEX86 of IPL, but not CL GDGTs, changed via production and differential degradation. [•] Good preservation of glyco GDGTs discourages use as biomarkers for live Archaea. [•] Harsh oxidation events can alter TEX86 and other proxy values of IPL GDGTs. [•] Distribution changes in IPL GDGTs can be caused by differential degradation. [Copyright &y& Elsevier]