Fluvial Response to a Period of Hydrometeorological Change and Landscape Disturbance in the Canadian High Arctic

Abstract

AbstractRecords of fluvial suspended sediment fluxes are sensitive indicators of hydrometeorological and permafrost change. Here we document the watershed‐scale suspended sediment flux response to a period of hydrometeorological change and landscape disturbance in two High Arctic rivers. Net in‐channel and extra‐channel sediment storage and changing hydrometeorological conditions dampen the downstream transport of increased sediment delivery from localized permafrost slope disturbances. Our results show that the impact of permafrost disturbance is likely a smaller effect than a shift toward a pluvially (rainfall) dominated hydrological regime in these environments. Suspended sediment transport is energy limited under contemporary hydrometeorological conditions, and the transition from a nival to pluvial dominated flow and sediment transfer regime will likely accelerate landscape change in the High Arctic.