Climate Instability during the Last Interglacial

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The Last Interglacial was characterized by the highest peak temperatures and sea level of at least the past 250,000 years, caused by increased Northern Hemisphere summer insolation and ocean- and land- feedbacks. Though not a strict analogue for future global projections, the Last Interglacial provides an invaluable observational context for climate instability during periods of 'excess' warmth. While a number of marine and terrestrial records suggest the presence of climate instability during the Last Interglacial, chronological uncertainties complicate an assessment of the local or regional significance of reported events. This projects aims to produce a 'stratigraphical Rosetta Stone' linking reconstructions of deep- and surface-water hydrography with regional vegetation change in the same deep-sea sequence from the south Portuguese margin; a key area for linking marine and terrestrial records and tracing millennial-scale variability. The increased resolution of the records will allow the detection of centennial-scale events and establish whether these are represented in both terrestrial and marine proxies. The most prominent abrupt climate events have usually been associated with glacial climates, and the canonical explanation of these events is that they are triggered by massive freshwater discharges into the North Atlantic. Evaluating and extending this paradigm to include climate instability during periods of excess warmth and reduced ice-volume is of particular relevance, especially in the context of future climate change.