Coastal Data Tools and Data Products for Coastal Protection as Climate Change Impacts Advance Kate Moran, Ocean Networks Canada Canada’s coastline areas are complex physiographic and, in many locations, multi-jurisdictional settings that are challenging to analyze for risks of climate impacts (storm surge and sea level rise) and natural hazards (tsunamis). This is particularly true for the southwestern mainland of British Columbia and Washington State.

To assess coastal impacts of this trans-boundary region, a collaboration among Ocean Networks Canada, Natural Resources Canada (NRCan), the Semiahmoo First Nation, the US National Oceanographic and Atmospheric Association (NOAA), and many other partners worked together to build a high-spatial resolution and seamless, coastal digital elevation model (DEM) that extends from coastal Washington State to the city of Vancouver.

DEMs are essential data products that are used to model tsunami, storm surge, and sea level rise inundation forecasting—essential for developing response and resilience plans for coastal climate adaptation. The DEM was developed at Ocean Networks Canada over a two-part, eight-day DEM workshop of geospatial specialists and engineers from the above-mentioned partner organizations. The workshop was part of a demonstration study under the Canadian Safety and Security Program Coastal Flood Mitigation Canada Project, led by NRCan. The output of the workshop was a dynamic coastal DEM data product (see figure).

The partners use the DEM to forecast inundation from Amante et al. (2020), Canada-United States Elevation Model Collaboration to Improve Tsunami Inundation Mapping, American Geophysical Union, Fall Meeting 2020, abstract #NH014-0008. A digital elevation model that stitched together bathymetric (offshore) data with topographic (onshore) data. The red circle shows the location of port and ferry infrastructure on the BC mainland. multiple types of tsunamis generated at the Cascadia subduction zone that includes a forecasted sea level rise component.

The DEM is also suited to forecasting inundation from storm surges (models have been completed by DFO and publications are pending), king tide events, and meteo- tsunamis to inform actions needed for building critical infrastructure and community resilience. It is highly recommended that this DEM, soon to be made more broadly available by NRCan, be used for continued modelling of coastal storm surge flooding scenarios to inform resilience decisions and actions.

For the highest sea level risk areas of Canada (e.g., areas of Atlantic Canada; Tuktoyuktuk), it is also recommended that support and incentives be provided for national and regional partners to convene to develop the high spatial resolution DEMs foundational datasets required for adaptation and resilience decision-making in those regions.