Coastal Erosion

The Arctic circumpolar coastline comprises a substantial portion of the world's coast, bounding the polar Arctic Ocean and including the islands of northern Russia, Svalbard, the Canadian Arctic Archipelago, the intricate coast of Greenland, and extensive mainland coasts of Siberia, Alaska, and Canada. Arctic coasts are located within a broad spectrum of oceano-graphic environments and thus exhibit a corresponding variety of shoreline geomorphology and geology. Examples of this variety range from tidewater glaciers and steep-walled fjords, to high rock cliffs banked with talus (rock debris), to low-relief coastal plain shores with a wide range of lithology, cryology, vegetation cover, shore-zone morphology, and erosion processes. Sediment production from the erosion of unlithified but frozen (ice-bonded) sediments on some Arctic coasts rivals or exceeds the inputs from large rivers such as the Lena, and the associated release of organic matter may be significant in the carbon budget of the Arctic Ocean. Some areas, notably in the central Canadian Arctic, are still rebounding from isostatic depression under the continental ice sheets of the last glacial maximum, with measured uplift rates as high as 1 m per century, while other parts of the Arctic coast are slowly submerging through a combination of crustal subsidence and rising sea level.

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