This study demonstrated that it is feasible to electronically transmit and grade retinal images remotely using the TOSCA process. Built-in quality assurance procedures proved acceptable.

ABSTRACT. The City of Iqaluit, Nunavut, is an expanding urban centre with important infrastructure located in the coastal zone. This study investigates the exposure of this infrastructure to coastal hazards (rising mean sea level, extreme water levels, wave run-up, and sea ice). Using a coastal digital elevation model, we evaluate the inundation and flooding that may result from projected sea level rise. Some public and private infrastructure is already subject to flooding during extreme high water events. Using a near upper-limit scenario of 0.7 m for relative sea level rise from 2010 to 2100, we estimate that critical infrastructure will have a remaining freeboard of 0.3-0.8 m above high spring tide, and some subsistence infrastructure will be inundated. The large tidal range, limited over-water fetch, and wide intertidal flats reduce the risk of wave impacts. When present, the shorefast ice foot provides protection for coastal infrastructure. The ice-free season has expanded by 1.0-1.5 days per year since 1979, increasing the opportunity for storm-wave generation and thus exposure to wave run-up. Overtopping of critical infrastructure and displacement by flooding of subsistence infrastructure are potential issues requiring better projections of relative sea level change and extreme high water levels. These results can inform decisions on adaptation, providing measurable limits for safe development.Key words: Arctic coast; adaptation planning; infrastructure; sea level rise; flooding; sea ice; climate change; coastal management RÉSUMÉ. La ville d'Iqaluit, au Nunavut, est un centre urbain en plein essor doté d'infrastructures importantes sur la zone côtière. Cette étude se penche sur l'exposition de cette infrastructure aux risques côtiers (niveau de la mer montant, niveaux d'eau extrêmes, vagues et glace de mer). À l'aide d'un modèle numérique de l'élévation côtière, nous évaluons les inondations et les submersions susceptibles de découler de la montée projetée du niveau de la mer. Certaines infrastructures publiques et privées sont déjà la cible d'inondations en présence de très hautes eaux. En nous appuyant sur un scénario dont la limite supérieure est de près de 0,7 m pour la hausse relative du niveau de la mer de 2010 à 2100, nous estimons que les infrastructures critiques auront un franc bord de 0,3 à 0,8 m au-dessus de la marée haute de vives-eaux, et une partie des infrastructures de subsistance sera inondée. La grande amplitude de la marée, le fetch limité sur l'eau et les larges battures intertidales réduisent le risque de l'impact des vagues. Lorsqu'elle est présente, la glace de rive offre une protection aux infrastructures côtières. Depuis 1979, la saison sans glace s'est prolongée de 1,0 à 1,5 jour par année, ce qui augmente la possibilité de la formation de vagues de tempête et, par conséquent, l'exposition aux jets de rive. La submersion des infrastructures critiques et le déplacement des infrastructures de subsistance par les inondations constituent des enjeux potentiels qui doivent faire l'obj...

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This report describes data collected during five field trips to Koojesse Inlet, Nunavut, between 2009 and 2011. These trips have expedition numbers 2009306, 2010307, 2011303, and 2011307 (includes 2 trips). Koojesse Inlet is in the northwestern end of Frobisher Bay on Baffin Island. Data were collected primarily on foot within the intertidal, but there are some boat-based datasets associated with expedition 2011307. Data collected include: RTK-GPS transects, sidescan sonar lines, single beam sonar lines, tide and wave recorder deployments, current profiler deployments, surface and grab sediment samples, underwater drop camera lines, and shallow sub-bottom profile lines. Results show a complex intertidal zone characterized by a higher slope beachface and ank face at the edge of the low-slope tidal at terrace, with varying concentrations of boulders. Sediment is a mixture of relict glaciomarine overlain by a shallow reworked sand/mud surficial layer. Sediment in the nearshore varies from fine silts to cobble/gravel deposits in the more exposed areas. This study was unable to resolve significant amounts of erosion on the tidal at surface, but the geomorphological evidence is irrefutably indicative of an erosional landform.

Tidal flats are widely distributed on high-latitude coasts, where sea ice processes have been invoked to explain the abundance and distribution of boulders. This study documents the surface morphology and sediment dynamics of a low-Arctic macrotidal system, the boulder-rich tidal flats of Koojesse Inlet, fronting the Nunavut capital, Iqaluit, on Baffin Island. This is a region of postglacial isostatic uplift and forced regression, with raised littoral, deltaic, and glaciomarine deposits. The spring-tidal range is 11.1 m and sea ice cover lasts roughly 9 months of the year. The extensive intertidal flats are up to 1 km wide, with a veneer of sand and gravel (including large boulders) resting on an erosional unconformity truncating the underlying glaciomarine mud, forming a terrace within the present tidal range. Over a three-year study, no consistent pattern of erosion or deposition was evident. Over a longer time scale, the concave hypsometry, low sediment supply, slight ebb-dominance of weak tidal currents, abrasion by wave-entrained sand, ebb-oriented ripples formed under subaerial drainage, and slumps on the terrace flanks are consistent with seaward hydraulic and gravitational sediment transport. These processes may be of greater importance than shoreward ice transport. This study underlines the importance of relict glaciomarine deposits, postglacial uplift, and falling relative sea level in the erosional development of these high-latitude tidal flats. Relative sea-level projections for Iqaluit are ambiguous, but a switch to rising sea level, if it occurs, combined with more open water and wave energy, could alter the foreshore dynamics of the system.