Changes to the Beaufort Sea shoreline occur due to the impact of storms and rising relative sea level. During the open-water season (June to October), storm winds predominantly from the north-west generate waves and storm surges which are effective in eroding thawing ice-rich cliffs and causing overwash of gravel beaches. Climate change is expected to be enhanced in Arctic regions relative to the global mean and include accelerated sea-level rise, more frequent extreme storm winds, more frequent and extreme storm surge flooding, decreased sea-ice extent, more frequent and higher waves, and increased temperatures. We investigate historical records of wind speeds and directions, water levels, sea-ice extent and temperature to identify variability in past forcing and use the Canadian Global Coupled Model ensembles 1 and 2 (CGCM1 and CGCM2) climate modelling results to develop a scenario forcing future change of Beaufort Sea shorelines. This scenario and future return periods of peak storm wind speeds and water levels likely indicate increased forcing of coastal change during the next century resulting in increased rates of cliff erosion and beach migration, and more extreme flooding.

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To better understand the reaction of Arctic coasts to increasing environmental pressure, coastal changes along a 210‐km length of the Yukon Territory coast in north‐west Canada were investigated. Shoreline positions were acquired from aerial and satellite images between 1951 and 2011. Shoreline change rates were calculated for multiple time periods along the entire coast and at six key sites. Additionally, Differential Global Positioning System (DGPS) measurements of shoreline positions from seven field sites were used to analyze coastal dynamics from 1991 to 2015 at higher spatial resolution. The whole coast has a consistent, spatially averaged mean rate of shoreline change of 0.7 ± 0.2 m/a with a general trend of decreasing erosion from west to east. Additional data from six key sites shows that the mean shoreline change rate decreased from −1.3 ± 0.8 (1950s–1970s) to −0.5 ± 0.6 m/a (1970s–1990s). This was followed by a significant increase in shoreline change to −1.3 ± 0.3 m/a in the 1990s to 2011. This increase is confirmed by DGPS measurements that indicate increased erosion rates at local rates up to −8.9 m/a since 2006. Ground surveys and observations with remote sensing data indicate that the current rate of shoreline retreat along some parts of the Yukon coast is higher than at any time before in the 64‐year‐long observation record. Enhanced availability of material in turn might favor the buildup of gravel features, which have been growing in extent throughout the last six decades.

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Yukon's Beaufort coast, Canada, is a highly dynamic landscape. Cultural sites, infrastructure, and travel routes used by the local population are particularly vulnerable to coastal erosion. To assess threats to these phenomena, rates of shoreline change for a 210 km length of the coast were analyzed and combined with socioeconomic and cultural information. Rates of shoreline change were derived from aerial and satellite imagery from the 1950s, 1970s, 1990s, and 2011. Using these data, conservative (S1) and dynamic (S2) shoreline projections were constructed to predict shoreline positions for the year 2100. The locations of cultural features in the archives of a Parks Canada database, the Yukon Archaeological Program, and as reported in other literature were combined with projected shoreline position changes. Between 2011 and 2100, approximately 850 ha (S1) and 2660 ha (S2) may erode, resulting in a loss of 45% (S1) to 61% (S2) of all cultural features by 2100. The last large, actively used camp area and two nearshore landing strips will likely be threatened by future coastal processes. Future coastal erosion and sedimentation processes are expected to increasingly threaten cultural sites and influence travelling and living along the Yukon coast.

Industrial activity in Canada's north is increasing, placing demands on the use of water from lakes to build ice roads. Winter water withdrawal from these lakes has the potential to impact overwintering fish. Removal of water from small lakes can decrease oxygen and habitat available to fish. To address this issue, a protocol has been developed by the Department of Fisheries and Oceans outlining water withdrawal thresholds. Bathymetric surveys are the traditional method to determine lake depth, but are costly given the remoteness of northern lakes. This paper investigates the use of satellite C-band synthetic aperture radar (SAR) remote sensing technology as a potential alternative or complement to traditional survey methods. Previous research has shown that a SAR can detect the transition from grounded to floating ice on lakes, or if a lake is completely frozen. Grounded ice has a dark signature while floating ice appears very bright in contrast. Similar results were observed for the datasets acquired in the study area. This suggests that lakes that freeze completely to the bottom can be identified using SAR. Such water bodies would not be viable fish overwintering habitat and can therefore be used as water sources without thresholds necessary. However, attempts to accurately calculate the depth of the ice at the grounded-floating ice boundary using bathymetric profiles acquired in the summer and lake ice thickness measurements from a reference lake near Inuvik proved to be unreliable.

Because the Yukon coast along the Beaufort Sea has the highest ground ice contents in the Canadian Arctic and, in addition, faces the direction of most effective storms, this section of coast is considered to be highly vulnerable to the effects of climate change. In order to gain insight into the regional coastal dynamics, a quantification of coastal change was undertaken that allowed the determination of spatial and temporal variability of coastal change along a 35 km long section of coast, stretching from Komakuk to the international border. Shorelines from several years between 1951 and 2009 were digitized from georeferenced aerial photographs and an ortho-rectified SPOT image. Shoreline change statistics were subsequently calculated using the Digital Shoreline Analysis System (DSAS) extension for Esri ArcGIS. Theodolite and real-time kinematic GPS data that was collected during several surveys between 1991 and 2012 at two Geological Survey of Canada (GSC) monitoring sites (Border site and Komakuk site) were analysed to provide higher temporal resolution of coastal change for the last two decades. Additionally, the field survey data enabled an assessment to be made of the contribution of geomorphic variables (i.e. beach slope, beach width, cliff slope, absolute cliff height, relative cliff height) towards explaining changes of coastal erosion. According to the findings, the mean annual erosion along the western Yukon coast has been -1.2 ± 0.4 m/a over the entire period of study, with the rates decreasing through time from -1.4 ± 0.6 m/a between 1951 and 1972, to -1.2 ± 0.5 m/a between 1972 and 2009. However, site specific investigations show that there are differences in the mean erosion rates and in temporal trends. To the west at the Border site, the mean annual erosion rate is -1.3 ± 0.3 m/a, and the rates have recently accelerated, while at Komakuk in the east of the study area, the mean annual erosion rate is -0.9 ± 0.2 m/a, with the rates decelerating over time. A comparison of these findings to erosion rates from the Alaskan Beaufort Sea coast indicates that there is a general spatial pattern of decreasing erosion rates from the west to the east. The quantified erosion rates also enabled the calculation of mean annual land loss between 1951 and 2009, which amounted to 4.5 ha/a. An analysis of the influence of shore profile parameters on mean annual erosion rates showed a statistically significant correlation between beach widths and erosion rates (r=0.84) at the Border site. There is also a strong but insignificant correlation between absolute cliff heights and erosion rates at the Border, but no correlations of shore profile parameters with erosion could be distinguished for the Komakuk site.

The North Shore of Prince Edward Island (PEI) is a sandy, multi-barred coast with limited fetch in most directions but open to the Gulf of St. Lawrence for several hundred kilometres to the north. In the fall and winter, storms tracking northwards across PEI and into the Gulf can bring sustained storm waves which generate currents capable of transporting sand in both the along- and across-shore directions. Mike21 is a commercially available combined wave, hydrodynamic and sand transport model that may be utilised to improve understanding of contemporary sand transport and possible implications of changing climate in the Brackley Bight area of the North Shore. This manuscript describes the development of a Mike21 model domain and optimal configurations of the Mike21 Spectral Wave, Hydrodynamic and Sand Transport modules appropriate to the study area. The sensitivities of several parameters in each module are tested. The Spectral Wave and Hydrodynamic modules are sensitive to estimates of bed roughness with optimal values considerably lower than published semi-empirical estimates. The Sand Transport module is sensitive to the input sediment transport tables and estimates of the maximum amount of vertical bed level change per day. Simulation of a 4-day moderate northeasterly storm is conducted and the results are compared to currents, waves, and tides measured by S4 current meters and the instrumented seabed lander RALPH during a sediment transport experiment in 1999. The model successfully simulates storm waves and currents and provides reasonable estimates of the amount and patterns of sediment transport.