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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.