Emily F Eidam, Nina Stark, Jaap H Nienhuis, Molly Keogh, Jeff Obelcz
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引用次数: 0
Abstract
Sediments covering Arctic continental shelves are uniquely impacted by ice processes. Delivery of sediments is generally limited to the summer, when rivers are ice free, permafrost bluffs are thawing, and sea ice is undergoing its seasonal retreat. Once delivered to the coastal zone, sediments follow complex pathways to their final depocenters-for example, fluvial sediments may experience enhanced seaward advection in the spring due to routing under nearshore sea ice; during the open-water season, boundary-layer transport may be altered by strong stratification in the ocean due to ice melt; during the fall storm season, sediments may be entrained into sea ice through the production of anchor ice and frazil; and in the winter, large ice keels more than 20 m tall plow the seafloor (sometimes to seabed depths of 1-2 m), creating a type of physical mixing that dwarfs the decimeter-scale mixing from bioturbation observed in lower-latitude shelf systems. This review summarizes the work done on subtidal sediment dynamics over the last 50 years in Arctic shelf systems backed by soft-sediment coastlines and suggests directions for future sediment studies in a changing Arctic. Reduced sea ice, increased wave energy, and increased sediment supply from bluffs (and possibly rivers) will likely alter marine sediment dynamics in the Arctic now and into the future.
期刊介绍:
The Annual Review of Marine Science, published since 2009, offers a comprehensive overview of the field. It covers various disciplines, including coastal and blue water oceanography (biological, chemical, geological, and physical), ecology, conservation, and technological advancements related to the marine environment. The journal's transition from gated to open access through Annual Reviews' Subscribe to Open program ensures that all articles are available under a CC BY license, promoting wider accessibility and dissemination of knowledge.