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Osborne, P.D. and Forest, A., 2016. Sediment dynamics from coast to slope - Southern Canadian Beaufort Sea. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 537-541. Coconut Creek (Florida), ISSN 0749-0208. Profound changes in cross-shelf sediment fluxes are anticipated in coming decades in the southern Canadian Beaufort Sea where an accelerated increase in temperature could lead to large changes in Arctic river hydrology and coastal-marine geomorphologic processes. In the past decade sediment exported to the Beaufort Shelf has increased while sea level pressure has increased accelerating the Beaufort Gyre, strengthening coastal upwelling and expanding the Mackenzie River plume offshore. Sea-ice extent has decreased while storminess has increased increasing wave action, coastal downwelling, current surge and resuspension and transport on the shoreface and shelf. This paper investigates mechanisms, quantities and rates of sediment transport operating in this cold continental shelf-slope environment. Past studies from more than 2 decades of research are compared with recent measurements to develop improved estimates of sediment sources, pathways, fate and fluxes across the shelf and slope. In particular, we explore connections between data from a long term mooring observatory deployed over the continental shelf and slope during the ArcticNet-Industry Partnership (2009-2011) and Beaufort Regional Environmental Assessment (BREA 2011-2015) to those acquired in studies focusing on nearshore and shoreface. Sediment fluxes from the Mackenzie River and erosion of permafrost coasts are compared with outer shelf-slope measurements of settling particles and near-bottom fluxes. In turn, the role of atmospheric and cryospheric processes in forcing sediment transfer from coast to slope is investigated to assess system response to changing climate and evaluate implications for marine hydrocarbon resource development along the continental margin of the Arctic Ocean. [ABSTRACT FROM AUTHOR]

Luz Clara, M.; Simionato, C.G.; D'Onofrio, E., and Moreira, D., 2015. Future sea level rise and changes on tides in the Patagonian Continental Shelf. We investigate the effect of the future sea level rise (SLR) on the propagation of tides in the Patagonian Shelf by means of numerical simulations. Using a barotropic implementation of the Model for Applications at Regional Scales (MARS), we obtain solutions for scenarios which represent the present condition and potential future SLRs of 1, 2, and 10 m. The effect of flooding of low-lying areas is studied, and its influence on the propagation of tides in the region is discussed. Due to the coastal morphological features and the sense of tidal wave propagation in the Southern Hemisphere, inundation does not significantly modify the solution in the Patagonian Shelf; nevertheless, results are substantially changed in the much lower Northern Argentinean Shelf, north of 40° S, where dissipation is increased. The amplitude of M2 responds to SLR in a spatially nonuniform manner. The response is nonlinear, particularly in regions close to the amphidromic points. Tidal dissipation by bottom friction increases consistently by 16% for the more extreme scenario with a generalized increment of tidal amplitudes, and therefore currents, over the Patagonian Shelf. Changes in the extension and position of tidal fronts are also explored. The results suggest that changes will be significant, with a reduction of the mixed areas in Cabo Blanco and San Sebastián and an increment of them in the vicinity of Península Valdés. Physical mechanisms that explain the observed modifications in the tidal regime are the changes with SLR of the speed of the tidal wave, the Rossby radius of deformation, the energy dissipation by bottom friction, and the resonant properties of the basin. Similarly to numerical studies performed for other coastal areas of the world, results indicate that important changes in the characteristics of tides can occur if SLR is large. [ABSTRACT FROM AUTHOR]