Predicting delta morphology and delta change on a global scale
By Jaap Nienhuis (Florida State University)
Fri Oct 6, 2017 10:30am - 11:30am Central Time
Host: John Goff
Abstract: Coastal deltaic change is expected to be one of the major Earth-surface hazards of the 21st century. We have quantified the effect of waves, tides, and fluvial sediment supply on delta morphology, and use this theory with global wave, tide, and fluvial sediment data to make morphologic predictions for Earth's deltas (n ~ 20000). For these deltas, we predict future changes in response to river damming, land-use changes, and climate change and find that many deltas with human-induced decreases in fluvial sediment loads will experience wave reworking into barrier islands or tide reworking into alluvial estuaries. Other deltas are projected to experience increased fluvial sediment flux, and, in some cases these growing deltas could transition to river-dominated morphologies. Our analysis provides opportunities for the inclusion of river deltas into Earth system and climate models, and for paleoenvironmental reconstructions based on delta sedimentology.
