Ice cover as a control on the morphodynamics and stratigraphy of Arctic deltas

Deltas are dynamic systems that can provide important information on past climate conditions. Arctic deltas have the potential to preserve information about climate in one of the most temperature-sensitive regions of the Earth. We present experimental results assessing the effects of ice cover on delta morphodynamics to identify signatures of ice-cover presence during deposition. Ice cover drives spatial variation in sediment transport on the subaqueous delta clinoform through sub-ice channels, which leads to the development of (1) extended delta lobes built by elongated, subaqueous sediment wedges and (2) bathymetry with increasing topographic roughness from the shoreline to a depth approximate to bottom-fast ice thickness. These unique seascape and stratigraphic features record past climate conditions, and can serve as indicators of climate change on vulnerable Arctic coasts.