Integration of heterogeneous terrain data into Discrete Global Grid Systems

ABSTRACT

The Canadian Digital Elevation Model (CDEM) and the High-Resolution Digital Elevation Model (HRDEM) released by Natural Resources Canada are primary terrain data sources in Canada. Due to their different coverage, datums, resolutions, and accuracies, a standardized framework for national elevation data across various scales is required. This study provides new insights into the adoption of Discrete Global Grid Systems (DGGS) to facilitate the integration of multi-source terrain data at various granularities. In particular, the Icosahedral Snyder Equal Area Aperture 3 Hexagonal Grid (ISEA3H) was employed, and quantization, integration, and aggregation were conducted on this framework. To demonstrate the modeling process, an experiment was undertaken for two areas in Ontario, taking advantage of parallel computing which was beneficial from the discreteness of DGGS cells. The accuracy of the modeled elevations was estimated by referring to the ground-surveyed values and was included in the spatially referenced metadata as an indicator of data quality. This research can serve as a guide for future development of a national elevation service, providing consistent, multi-resolution elevations and avoiding complex, duplicated pre-processing at the user’s end. Future investigation into an operational integration platform to support real-world decision-making, as well as the DGGS-powered geospatial datacube, is recommended.

KEYWORDS:

• Discrete global grid systems
• terrain data
• data integration
• national elevation service
• multi-resolution elevation
• parallel computing

Acknowledgments

We acknowledge the technical advice from the Research Computing Services at the University of Calgary. We appreciate Natural Resources Canada with the contribution number: 20210033. We also thank Dr. Titus Tienaah for his valuable insights.

Data availability statement

The data that support the findings of the experiment in this study are available with the identifier 10.5281/zenodo.4718019. The original Canadian Digital Elevation Model data can be obtained via the Geospatial-Data Extraction tool in Canada’s Open Government Portal: https://maps.canada.ca/czs/index-en.html. The High Resolution Digital Elevation Model data (Digital Terrain Model) are available at: https://ftp.maps.canada.ca/pub/elevation/dem_mne/highresolution_hauteresolution/dtm_mnt. Ground control points are accessible using COSINE, Ontario’s geodetic control database, on the website of Ontario Ministry of Natural Resources and Forestry: https://www.lioapplications.lrc.gov.on.ca/COSINE/index.html?viewer=COSINE.OntarioViewer&locale=en-CA.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the Canadian Natural Sciences and Engineering Research Council (NSERC) Discovery Grant program.  under Grant RGPIN/03977-2019.