The future of fluvial sediment delivery to deltas
Abstract: This research investigates fluvial sediment fluxes under environmental changes to assess the global sustainability of delta environments under potential future scenarios up to 2100. Factors such as subsidence and sea level rise cause deltas to sink relative to sea level if adequate sediment is not delivered to and retained on their surfaces, resulting in flooding, land degradation and loss. The future of fluvial sediment fluxes, a key mechanism for sediment delivery to deltas, is uncertain due to complex environmental changes which are predicted to occur during the coming decades. Climate change, reservoir construction, and population and GDP (as proxies for other anthropogenic influences) change datasets forced the global numerical model WBMsed, producing fluvial sediment fluxes under 12 scenarios of climate and socioeconomic change which are used to assess the future sustainability of 47 deltas. The results show decreased sediment delivery to most deltas during the coming decades, primarily due to dam construction and socioeconomic change. This suggests that deltas may be unsustainable environments if management plans are not significantly altered.
Frances Dunn is a postdoctoral researcher with DECCMA (Deltas, Vulnerability and Climate Change: Migration and Adaptation) looking at subsidence and physical adaptation mapping. Frances is also currently finishing her PhD, which is focused on modelling multidecadal fluvial sediment fluxes to deltas under future environmental changes. Her background is in physical geography, with a BSc in Geography and an MSc in Environmental Modelling, Monitoring, and Reconstruction from the University of Manchester.