Helena Alexanderson

Loess-palaeosol sequences (LPS) are among the most continuous terrestrial archives of Quaternary climate change. Their widespread distribution, high accumulation potential, and sensitivity to environmental variability make them critical for reconstructing past dust fluxes, wind regimes, and regional ecosystem responses. However, the reliability of such reconstructions is fundamentally constrained by the quality and resolution of the underlying chronology. Even minor dating uncertainties can translate into significant errors in calculated sedimentation rates and dust mass accumulation rates (MARs), limiting the ability to compare records across regions or to global climate archives. Our research focuses on refining luminescence dating techniques and applying advanced Bayesian age-depth modelling to loess deposits in the Carpathian and Wallachian Basins. By constructing higher-resolution chronologies than previously available, we are able to portray more continuous and internally consistent records of sediment accumulation covering the later stages of the last glacial cycle and the Holocene. This approach also reveals discrepancies with earlier, lower-resolution studies and helps to identify processes such as partial bleaching, post-depositional mixing, or local geomorphological disturbance that can compromise loess chronologies. A central outcome of this work is the improved reconstruction of dust flux variability through time. Our results show that MARs do not always follow simplified expectations of high dust input during glacials and low input during interglacials. Instead, distinct peaks and fluctuations suggest the importance of regional controls such as palaeowind intensity, sediment availability from large river systems, and the trapping efficiency of local landscapes. These findings highlight the necessity of considering both global climate drivers and local environmental settings when interpreting loess records. The broader aim of our research is to integrate refined chronologies and dust flux reconstructions from across the Carpathian and Wallachian Basins, establishing a framework for comparing loess archives at both regional and continental scales. By doing so, we provide new insights into the timing, magnitude, and variability of past atmospheric dust activity, while contributing to the development of loess stratigraphy as a robust tool for Quaternary paleoenvironmental reconstruction.