How rivers remember: the effects of flow history on sediment mobility in gravel-bed rivers - Claire Masteller, Washington University in St. Louis
Claire Masteller, Assistant Professor of Earth and Planetary Sciences, Washington University in St. Louis
Abstract: Rivers transmit environmental signals across landscapes. In the wake of a changing climate, predicting river channel response to variations in flow magnitude and flood frequency is of significant importance for floodplain communities and ecosystems. As these environmental perturbations propagate across a drainage basin, it’s important to consider the role of prior flow history in a channel when predicting its future evolution. However, widely used models for fluvial sediment transport currently do not integrate these history effects. This omission represents a fundamental, outstanding knowledge gap in earth surface processes.
In this talk I will focus on the process of bedload sediment transport in gravel-bed rivers, where memory effects are observed over a variety of time-scales. I will first discuss the origins of memory in gravel bed rivers, using results from a series of laboratory flume experiments. I will then apply these new insights to a unique, continuous record of coarse sediment transport to quantify the thresholds for memory formation and destruction in a steep mountain stream. I will discuss the development and implementation of a history-dependent function to better describe sediment mobility by accounting for these memory effects.
About the Speaker: Claire Masteller started as an Assistant Professor of Earth and Planetary Sciences at Washington University in St. Louis just this last year. She received her PhD in Earth and Planetary Sciences at the University of California in Santa Cruz in 2017 and her BA in Earth Science at the University of Pennsylvania in 2012. She spent time as a post-doctoral researcher at GFZ - German Research Center for Geosciences in Potsdam Germany from 2017-2019. Masteller is broadly interested in sediment transport and erosion mechanics and their role in driving landscape evolution. She uses interdisciplinary methods to address research questions across a wide range of spatial and temporal scales.