Title: Compilation, normalization, and merging of datasets comprising the Canada west coast digital elevation model -- Description: 1. The data were downloaded and compiled from original data sources in their original formats and resolutions.

2. All processing of the data were performed in ArcGIS 10.7 and ArcGIS 10.8

3. All data were projected into a common map projection, in this case a NAD83 BC Albers with a central meridian of -126, the standard projection of the BC Government.

4. All data were up sampled or down sampled to a common resolution of 10 meters using appropriate resampling algorithms.

5. Where necessary, data elevations were re-calculated to the vertical chart datum used by the Canadian Hydrographic Service.

6. Data were merged into a continuous elevation surface.

7. The elevation surface was hillshaded using ArcGIS to create a shaded relief layer.

8. A source map was compiled from the vectorized polygons of the original data extents.

9. Metadata were compiled using the NRCan LCNP online metadata editor.

Government of Canada Data Sources:

Data sources from Canadian Hydrographic Service include multibeam sonar bathymetry surveys collected between 1997-2024 at resolutions ranging from 1 - 5 metres

Data sources from Department of Fisheries and Oceans include a coastal digital elevation model integrating ocean bathymetry and land topography described in Canadian Technical Report of Fisheries and Aquatic Sciences 3321

Natural Resources Canada data include a regional digital elevation model developed from CHS contour data in 1999 originally gridded at 75 meters.

Data sources from Ocean Networks Canada include a seamless digital elevation model of the British Columbia lower mainland developed during a workshop at ONC in Sept/Oct 2019 using Greater Vancouver municipal LiDAR datasets, NRCan regional multibeam mosaics developed from CHS multibeam survey data, and airborne bathymetric LiDAR.

Data sources from Washington State Department of Natural Resources

LiDAR data downloaded from the Washington Lidar Portal https://lidarportal.dnr.wa.gov/#48.50159:-122.92946:10

Original DTM data were 3 meter resolution.

In 2025, 118 new CHS multibeam surveys from the 2022, 2023 and 2024 field surveys were added to the compilation. Also added was a 2022 multibeam survey from the GEOMAR Helmholtz Centre led by Dr. Michael Riedel aboard the German M.V. Sonne.