Determine sensitivities of terrestrial environments to natural drivers and human impacts on human-relevant and geological timescales.

We use terrestrial sedimentary archives, mainly annually laminated lacustrine sediments to reconstruct changes in landscapes and ecosystems during past climatic intervals. Annually resolved archives can resolve past changes on human relevant time scales and can be used as analogues of the present climate warming. For our reconstructions we use a combination of micro-facies analyses, sedimentology, chemical sediment characterisation by X-ray fluorescence (XRF) scanning, sediment metal isotopes (neodymium, strontium, iron), and stable-isotope ratios of sediment (carbon, oxygen) and biomarkers (hydrogen and carbon). Together with varve chronologies, these analyses can track the pace and sensitivity of hydroclimate and ecosystem changes, with minimal chronological uncertainties. Finally, we use tephra-chronology to link and match regional records and investigate the spatial variability and time-transgression of past climatic changes.

Our reconstructions focus on abrupt climatic events such as the Younger Dryas cold event that lasted approximately 1150 year, and occurred during the Late Glacial warming between 12.6 and 11.5 thousand years ago. Additionally, we focus on periods past warming climates as the Holocene climatic optimum and past interglacial periods of Marine Isotope Stages (MIS) 5 between 130 and 80 thousand years ago and MIS7 between 247 and 182 thousand years ago as analogues of the current anthropogenic global warming.

These reconstructions aim to determine the feedbacks between palaeohydrological changes and biogeochemical fluxes, by tracking changes in moisture and sediment dynamics, precipitation intensity, and evapo-transpirative processes. We focus especially on the spatial variability of hydrological changes to determine regional vulnerabilities to global warming. Further, we provide detailed climatic and environmental frameworks to determine the effects of such changes on past human populations and the way by which humans have modified landscapes since the onset of the Holocene.