Arctic Deltas
Keywords:
Arctic, Alaska, Canada, Russia, coastline, deltas, deltaic processes, permafrostAbstract
Arctic river deltas are among the most unique and fragile of deltas to be found on earth. Leading to this uniqueness and fragility are the interactions between geologic, oceanographic, climatologic, biologic, and cryospheric activities that occur in high latitudes. These interactions are analyzed at both regional and local levels with respect to their influence on delta formation. Specific morphological forms, such as ice-wedge polygons, and processes, such as thermoerosion, that are associated with permafrost are identified. Arctic deltas, including the Ob, Lena, Yenisey, Mackenzie, Yukon and Colville, are discussed illustrating the diverse range of variables affecting deltaic processes. Variables considered include age, size, shape, discharge, sediment load and surface forms. Current anthropogenic impacts on deltaic resources, such as construction associated with hydrocarbon production, are considered as is the potential for change that could result from a rising sea level.