Relative sea-level projections are provided for 59 locations in Canada and 10 in the adjacent mainland United States (New England and Washington State) through the 21st century, relative to 1986-2005. The projections are based on the Representative Concentration Pathway (RCP) scenarios of the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC AR5). They include contributions from thermal expansion of the ocean (steric effect), land ice melting and discharge, and anthropogenic influences. The global mean sea-level projection for RCP8.5, the largest emissions scenario, at 2100 is 74 cm (5%-95% range is 54 to 98 cm). Global Positioning System (GPS) measurements of vertical land motion are incorporated into the relative sea-level projections. In the regions presented here, vertical land motion, largely arising from glacial isostatic adjustment, plays a prominent role in determining projected relative sea-level change. On the east coast, crustal subsidence, combined with dynamic oceanographic changes, generates relative sea-level projections that are similar to or larger than the global mean projections in large parts of Atlantic Canada and New England. On the west coast, most relative sea-level projections are smaller than the global means, although some sites in Washington State and southern British Columbia feature relative sea-level projections similar to the global values. The largest variation in projected relative sea-level rise occurs in the Arctic, owing to the very large spatial differences in present-day crustal uplift due to glacial isostatic adjustment. Here, projected relative sea-level at 2100 varies from around 1 m of sea-level fall (median values) where land is rising quickly on Hudson Bay, while it reaches about 70 cm of sea-level rise on the Beaufort coast where the land is subsiding. A scenario featuring partial collapse of a portion of the West Antarctic Ice Sheet provides an additional 65 cm of sea-level rise to RCP8.5, and may be appropriate to consider when tolerance to the risk of sea-level rise is low. The relative sea-level projections given here only provide a trajectory through this century, but the IPCC AR5 projects continued global sea-level rise in coming centuries. As understanding improves of the various components of sea-level rise, it will be necessary to update, on an occasional basis, the relative sea-level projections and re-evaluate the implications for infrastructure, habitat, and marine navigation.

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The inner Northeast Newfoundland Shelf and coast were mapped to determine the potential of the region to host marine placer minerals, particularly gold. Five units were mapped: unit 1, bedrock; unit 2, glacial diamicton; unit 3, glaciomarine mud; unit 4, postglacial mud; and unit 5, postglacial sand and gravel. These units occur in five zones defined by depth, as follows: 1) deep, offshore basins contain thick deposits of glaciomarine, gravelly, sandy mud overlain by postglacial mud; 2) in shallower water, these units have been winnowed by currents; 3) above a depth of about 200 m, the seabed has been furrowed and pitted by grounded icebergs; 4) above a depth of 70 m the seabed is highly mobile; 5) the intertidal/supratidal zone is narrow and rocky, except along The Straight Shore. Relative sea level has been falling throughout postglacial time in the west, but in the east it dropped to -20 m about 8.7 ka before rising again. Fiords contain thick deposits of glaciomarine mud, capped by thin, postglacial mud. Shallow, outer-fiord areas are heavily imprinted by iceberg furrows and pits. In zone 4, which has the highest potential to host marine placers, extensive gravel and sand deposits occur on the wide, shallow, inner shelf between Cape Freels and Hamilton Sound, but no gold has been found in samples, likely because of a lack of gold mineralization onshore. Some gold was found at Deer Cove in Baie Verte, although the volume is small and the grades low.

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