Sediment transport in ice-affected rivers

SummaryThis paper presents a comprehensive review of sediment transport in ice-affected rivers by documenting a range of unique ice and sediment transport processes. In cold regions during winter, high sediment transport rates can occur under specific ice conditions, even if the channel discharge is low. River ice directly displaces and carries sediment, and some ice processes can move boulder-sized sediment, contributing to the sculpting of river channels in ways water alone could not. Special attention is directed to the ice breakup period, during which most dynamic ice processes take place and when sediment supply to river channels is maximized. Also discussed are the time and space scales over which ice processes affect sediment transport. Moreover, a global framework that describes the interconnectivity of climate, river discharge, channel morphology, in-stream hydraulics, and sediment transport response is proposed. Within this framework, ice processes are given a central function, as they influence and are affected by sediment transport, hydrological conditions, and channel morphology. A segment of this work reviews and explores the interconnectivity between river ice processes and river discharge as well as between river ice processes and channel morphology. The proposed framework represents a practical tool for a wide range of cold region river scientists and engineers, particularly in light of climate change.

► Sediment transport in ice-affected rivers during winter has been largely overlooked. ► Various ice and winter-related processes definitely promote sediment transport. ► River ice is influenced by and can perceptibly affect the hydrological regime. ► There is an evident feedback loop between river morphology and ice processes. ► A comprehensive framework is proposed to understand winter sediment transport.