Sediment-transport processes have been studied within a lagoon-barrier island environment on the Alaskan Arctic Ocean coast. In this area, active transportation is confined to the period from June to October. Analysis of aerial photographic surveys during the period 1949-1971 indicates accretion on one island (Thetis) at a mean rate of 2,580 sq m/year, whereas an adjacent island (Pingok) has been breached and eroded at both the western and eastern extremities. Recent studies of seasonal shoreline erosion demonstrate that more than 10 m may be removed within a single season. Erosion rates for the eastern end of Pingok Island are calculated to be at least 3,000 sq m/year. Littoral sediment transport along the northwestern and northeastern shores, landward of the lagoon (Oli tok Point), ranges from 0 to 38 sq m/day with current velocities of 0-75 cm/second. Most of the coastal spits and shoals in this area trend west. The prevailing winds are from the east and northwest. Overflow during breakup, thermal erosion of beach cliffs, normal fluvial and nearshore sedimentary processes, summer storms, and ice-rafting are the predominant mechanisms of erosion and deposition.

The more significant sediment movements here represent a net transport from east to west, especially on the barrier islands. These movements are considered to be due to the catastrophic effects of summer storms, for rates of littoral transport are lower, and the season for this transport is relatively short, in comparison with conditions in temperate areas.

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