Predicting Coastal Deltaic Change on a Global Scale

Florida State University, Tallahassee FL

Investigators

Abstract

Coastal erosion is expected to be a major Earth-surface hazard in the 21st century, in part because sea-level rise, river damming, and land-use changes will affect the sediment budget of river deltas. Predictions of coastal change are critical for both long-term coastal management and the assessment of future coastal hazards, particularly in relation to climate change. This project will highlight where and how fast deltas are expected to be drowned by sea-level rise, eroded by waves into spits and barrier islands, or shaped by tides into alluvial estuaries. Such a unified, global picture can also be used to assess how uncertain future scenarios, driven by for example carbon emissions, will affect coastal change. To achieve broader impacts the investigators will collaborate with Deltares and the United Nations to reach decision makers on a local and global scale by developing the Delta Forecast tool, a new interactive web-based map that will highlight projected changes to river deltas. This tool will accompany a white paper on future deltaic change published with the United Nations University. All model codes and data will be made available to the scientific community in a public repository. This research will support one postdoctoral researcher, one graduate student, and one undergraduate student. The project will set up international and interdisciplinary collaborations. River deltas form when sediments from a river are deposited close to the river mouth. Deltas exist in a wide variety of shapes and sizes partly because ocean waves, tides, and sea-level fluctuations move sediments within the coastal zone. This variability has made it challenging to predict future coastal erosion and deposition around river deltas. This project will create a global computer model of river delta change to: (i) predict modern river delta shape by calculating sediment movement due to the river, ocean waves, tides, and sea-level fluctuations, and to (ii), incorporate predictions of changes to these forces and assess future river delta change. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.