The Dalhousie Libraries’ GIS Centre invites you to explore the geography of Halifax’s past with their recreation of historic images in 2- and 3-D to mark 100 years since the Halifax Explosion.
Curated by James Boxall, the exhibit in the Dalhousie Art Gallery, From 2D to 3D: Mapping Halifax Over Time, allows you to view streets, buildings, and other topographic features depicting the north-end of Halifax after the explosion on December 6, 1917.
The three dimensional image of the Halifax Explosion site was created using the original fire insurance plans from 1914. These were reformatted in ArcGIS to create building and road footprints. The maps were then ‘joined’ to the ‘real’ world, forming a database which included street addresses and building heights. The time to generate new data from the original map was two months of painstaking work by student interns Cam Robertson (MPLAN) and Shanni Bale (MREM).
The structures were then georeferenced and attached to the Devastation Map where the outlines of buildings that were either totally or partially destroyed could be seen. Once the maps were joined into one database, the GIS Centre was able to use building heights and locations to match with the full digital elevation model (DEM) which uses bare earth altitude from LiDAR Data (light detection/lasers from aircraft surveys). That gave the GIS Centre a 3D form to attach all data sources.
Other researchers added data which expanded the benefits of what was being created within the GIS Centre (e.g. information related to the Halifax Explosion Relief Commission). This project was also the GIS Centre’s first Historical GIS under the rubric of providing information and data access, and knowledge translations within digital scholarship, so adding other users/creators was a welcomed outcome.
Additionally, the project gave students the opportunity to test new software and data formats along with historical images, maps and recreated data. At completion, the students involved saw this effort as the beginning of a historic atlas framework for Halifax.
From now until December 17 this map visualization can be seen in the Dalhousie Art Gallery from 11 a.m.–5 p.m. Tuesday–Friday, and noon–
5 p.m.on Saturday and Sunday.