Hakai Topographic Basemap

Hakai Topographic is a basemap made to enhance and compliment ESRI topographic for the greater Hakai study area.

This basemap is meant to be used only for visualization purposes and for understanding the spatial context as it relates to topographic relief.

Hakai Topographic has 12 layers of data. Four of those layers are raster DEM / Hillshade merge datasets. The following list details each layer and their origins:

1) Land Mask

Land Mask is derived from the Greater Hakai Area of Interest Boundary - the British Columbia shoreline dataset (BC DATA - 2013). 2012 + 2014 LiDAR datasets have been used to extract the shoreline for Calvert Island area. A combination of different elevations around the island have been used to create the shoreline.

2) Streams

For areas outside of Calvert Island streams are based on the British Columbia Fresh Water Atlas (http://geobc.gov.bc.ca/base-mapping/atlas/fwa/). FWA is dissolved and scale dependant. Dissolved based on stream order so relative stream sizes can be reflected in the basemap. No alterations have been made to the streams data although some errors are observed on smaller order streams. For Calvert Island 2012 + 2014 LiDAR hydrologic modeling outputs have been used as a best approximation to the occurrence of streams. One scale uses only stream order >3 up to 1:144*** scale. The second uses all (1-8) stream orders for scales DEM (Digital Elevation Model) LiDAR Based (Calvert Area).

A 3m topographically complete, hydro-flattened, bare-earth DEM produced from a merging of 2012 + 2014 LiDAR data by means of Natural Neighbours interpolation.

--> Hillshade (LiDAR Based – Calvert Island)

Hillshade derived from the above-mentioned LiDAR based DEM.

5) Gamma Corrected, Orthorectified Hillshade-Elevaation Tint Fussion for the land component excluding Calvert Island

Following http://www.esri.com/news/arcwatch/0612/using-image-analysis-functions-to-display-layer-tints-on-hillshades.html. a tint fusion was generated for the land copmonent excluding Calvert Island, making use of the following layers and a custom colour ramp for the DEM tint.

--> DEM (Digital Elevation Model) Based.

A DEM was resampled to 5 meters to improve the look by giving it a smoother appearance. A clip was used (using the land mask) to smooth the edges of the shoreline. Calvert Island was erased so the Hakai LiDAR dataset could be used to enhance the spatial resolution of the final product.

--> Hillshade

A Hillshade model was developed in ArcGIS for Desktop from the DEM. A raster calculator was used to convert “no-data” to a value of 180 (flat land). A clip to the shoreline (land mask) was used to ensure no bleeding of no data would impact the look of the final basemap.

6) Trails

Note: Many of the trails listed are not maintained by Hakai. Please use at your own risk. Trails data was gathered using a handheld GPS. Accuracy is estimated to be roughly 2 meters. Edits made by HAKAI SPAR to delete beach sections. Other trails do exist, but are not open to the public because they may damage sensitive habitats or disturb species of interest.

7) Buildings

Digitized building footprints based on roof line of 2012 orthophotos. Other structures are included such as yurts, britcos, and solar panels. Accuracy is only as good as the geolocation of the 2012 orthophotos. Buildings layer only covers the Calvert Island field station.

8) Ocean

Ocean mask Is the inverse of the land mask data. An erase tool was used with the Greater Hakai Area of Interest and the Land Mask layer to ensure no gaps existed between the datasets.

9) Bathymetry classes polygons

In order to attempt seamless integration with the underlying ESRI Topographic Basemap (http://services.arcgisonline.com/ArcGIS/rest/services/World_Topo_Map/MapServer), which shows different coloured polygons at scales 1:200,000 to 1:100,000 for the ocean component denoting ocean depth, 5 "depth classes" going from most-shallow to deepest were derived from a 25m Bathymetry dataset, and polygons were generated based on these class intervals. The class interval values were derived by use of a Natural Breaks (Jerks) classification applied to the Bathymetry Model. The obtained polygons closely match those shown by ESRI for the entire Earth; however given that the 5 classes utilized in Hakai Topographic originate from a different dataset and of different extent than that employed by ESRI, some minor inconsistencies exist between ESRI and Hakai Topographic, and this data is only destined for visualization and contextrualization purposes.

10) Contour 20m

Contours dissolved to improve online efficiency.

11) Contour 20m Calvert

20 meter contours that are LiDAR derived for the Calvert / Hecate area. Based on a 3 meter DEM (see #4 above)

12) Contour 5 m Calvert

LiDAR based for the Calvert / Hecate area. Based on a 3 meter DEM (see #5 above) 5 meter contours that are LiDAR derived for the Calvert / Hecate area. Based on a 3 meter DEM (see #4 above).

Access and Use

Licence: Appropriate credit must be given to Hakai Institute and the authors of the dataset.

Data and Resources

Dates

Metadata Created October 26, 2018, 22:48 (UTC)
Metadata Updated October 26, 2018, 22:48 (UTC)
Reference Date(s) 2015-08-14 (Creation)
2015-08-14 (Publication)
2015-08-14 (Revision)
Frequency of Update annually
Metadata Date October 27, 2015, 11:29 (UTC)

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Dataset extent

Map data © OpenStreetMap contributors

Additional Info

Field Value
Contact Email data@hakai.org
encoding utf8
metadata-language eng
progress completed
resource-type dataset
Responsible Party Hakai Institute (Point of Contact, Processor)