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.

摘要

加拿大自然资源部发布的加拿大数字高程模型（CDEM）和高分辨率数字高程模型（HRDEM）是加拿大的主要地形数据源。由于它们的覆盖范围、基准面、分辨率和精度不同，因此需要一个针对不同尺度的国家高程数据的标准化框架。这项研究为采用离散全球网格系统 (DGGS) 以促进各种粒度的多源地形数据的集成提供了新的见解。特别是采用了二十面体斯奈德等面积孔径 3 六边形网格（ISEA3H），并在该框架上进行了量化、积分和聚合。为了演示建模过程，在安大略省的两个地区进行了一项实验，利用并行计算，这得益于 DGGS 单元的离散性。模拟高程的准确性是通过参考地面测量值来估计的，并包含在空间参考元数据中作为数据质量的指标。这项研究可以作为国家高程服务未来发展的指南，提供一致的、多分辨率的高程，并避免在用户端进行复杂、重复的预处理。建议对支持现实世界决策的操作集成平台以及 DGGS 支持的地理空间数据立方体进行未来调查。这项研究可以作为国家高程服务未来发展的指南，提供一致的、多分辨率的高程，并避免在用户端进行复杂、重复的预处理。建议对支持现实世界决策的操作集成平台以及 DGGS 支持的地理空间数据立方体进行未来调查。这项研究可以作为国家高程服务未来发展的指南，提供一致的、多分辨率的高程，并避免在用户端进行复杂、重复的预处理。建议对支持现实世界决策的操作集成平台以及 DGGS 支持的地理空间数据立方体进行未来调查。