SEA-ICE INFLUENCE ON ARCTIC COASTAL RETREAT.

Erk Reimnitz; P. W. Barnes

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USGS · 70015240

SEA-ICE INFLUENCE ON ARCTIC COASTAL RETREAT.

Erk Reimnitz·P. W. Barnes

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Abstract

Recent studies document the effectiveness of sea ice in reshaping the seafloor of the inner shelf into sharp-relief features, including ice gouges with jagged flanking ridges, ice-wallow relief, and 2- to 6-m-deep strudel-scour craters. These ice-related relief forms are in disequilibrium with classic open-water hydraulic processes and thus are smoothed over by waves and currents in one to two years. Such alternate reworking of the shelf by ice and currents - two diverse types of processes, which in the case of ice wallow act in unison-contributes to sediment mobility and, thus, to sediment loss from the coast and inner shelf. The bulldozing action by ice results in coast-parallel sediment displacement. Additionally, suspension of sediment by frazil and anchor ice, followed by ice rafting, can move large amounts of bottom-derived materials. Our understanding of all these processes is insufficient to model Arctic coastal processes.

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Erk Reimnitz, P. W. Barnes. 1987. SEA-ICE INFLUENCE ON ARCTIC COASTAL RETREAT.. https://pubs.usgs.gov/publication/70015240

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