The rock coasts of polar and sub-polar regions
Polar and subpolar coasts are distinctive owing to the presence of ice on land as permafrost, ground ice and glacier ice, and in the sea as tidewater glaciers, icebergs, ice shelves and sea ice. Most of these coasts remain glaciated or are recently deglaciated so their geomorphology carries a strong glacial signature. The morphogenetic environment of polar and subpolar coasts is dominated by extreme seasonality with winter development of sea ice and a shore-fast ice foot that excludes wave activity and is primarily protective. However, sea ice may also be erosional at any time of year but is most effective as an erosional agent on polar coasts between freeze-up and break-up, when wave activity forces sea ice to repeatedly impact the shore. Depending on latitude, the short summers are characterized by wave and sea ice erosion at high latitudes and by wave activity at lower latitudes. The contribution of frost weathering to cliff and shore platform development in polar and subpolar rock coasts is unclear, but is likely to be an important influence. Rock coasts are widespread in the Arctic and sub-Arctic, including Iceland, and in the Antarctic and sub-Antarctic the limited ice-free coast is almost entirely rock-dominated.
Figures & Tables
Rocky landforms dominate large portions of the world's coast. Cliffs and shore platforms form spectacular landscapes, yet when compared to other landforms they are relatively unstudied with many contemporary controversies dating back to the mid-nineteenth century. The past decade has seen a reinvigoration of research driven by advances in technology that now enable precise measurements of erosion to the micron scale and quantification of wave energy onto and through cliff edifices to be made, as well as being able to directly date rock surfaces. In order to integrate this diverse range of research this volume's regional approach first integrates the latest data with longstanding theory and then analyses this research through the boundary conditions that exist in each area. The volume brings together the research leaders in the field; includes chapters on nearly all the major rock coasts of the world and identifies future research needs.