Multi-decadal coastal evolution of a North Atlantic shelf-edge vegetated sand island — Sable Island, Canada

Impacts from a changing climate, in particular sea-level rise, will be most acutely felt on small oceanic islands. A common configuration of mid-latitude islands is the sandy barrier island. Sable Island, Nova Scotia, Canada vegetated sand island near shelf edge, 160 km nearest point land, that morphologically similar to This study uses 60 years airphoto records analyse changes coastline position through digitized shore and vegetation (foredune proxy) lines. Rates coastal movement are analysed model future (2039) configuration. The analyses suggest majority Island retreat, with net retreat south side only partially offset by modest advance north side. different morphologies beach–dune systems South Beach North Beach, driven incident wind waves, yield these responses. Projected loss 10 ha 2039 climax heath vegetative community shoreline suggests trend toward instability due migration. Island-wide data set trends show support for two but complementary hypotheses about whole-island evolution: (1) mobile via bank migration driving southern experiencing sediment transport east, or (2) generally immobile losing subaerial sediments (and thus shrinking) likely ongoing accelerating) rise.