RDF and discrete global grid systems

Notes on discrete global grid systems, identifiers, and RDF.

One way to handle geospatial data in RDF is to bin point data into cells of a discrete global grid system (DGGS), and have unique identifiers for each cell in the grid. For example, Adams (2016) describes Wāhi which has URLs like http://dg3.cer.auckland.ac.nz/isea3h/11.25_58.2825/7/cell/1001 (server doesn’t seem to be working right now). Mocnik (2018) proposes a different identifier scheme that encodes cell coordinates in the identifier, which then helps displaying the cells (given the identifier we can retrieve the cell).

DGGS

SNYDER, J. P. (1992). An Equal-Area Map Projection For Polyhedral Globes. Cartographica: The International Journal for Geographic Information and Geovisualization, 29(1), 10–21. doi:10.3138/27h7-8k88-4882-1752

Sahr, K., White, D., & Kimerling, A. J. (2003). Geodesic Discrete Global Grid Systems. Cartography and Geographic Information Science, 30(2), 121–134. doi:10.1559/152304003100011090

SNYDER, J. P. (1992). An Equal-Area Map Projection For Polyhedral Globes. Cartographica: The International Journal for Geographic Information and Geovisualization, 29(1), 10–21. doi:10.3138/27h7-8k88-4882-1752

Code

DGGRID

dggridR: Discrete Global Grids

Geoscience Australia rHealPIX version of DGGS

H3: A Hexagonal Hierarchical Geospatial Indexing System

Identifiers

Mocnik, F.-B. (2018). A novel identifier scheme for the ISEA Aperture 3 Hexagon Discrete Global Grid System. Cartography and Geographic Information Science, 1–15. doi:10.1080/15230406.2018.1455157

Adams, B. (2016). Wāhi, a discrete global grid gazetteer built using linked open data. International Journal of Digital Earth, 10(5), 490–503. doi:10.1080/17538947.2016.1229819

Applications

Frankenplace

Searching Wikipedia geographically http://www.frankenplace.com

Adams, B., McKenzie, G., & Gahegan, M. (2015). Frankenplace. Proceedings of the 24th International Conference on World Wide Web - WWW ’15. doi:10.1145/2736277.2741137

Wāhi, a discrete global grid gazetteer built using linked open data

Adams, B. (2016). Wāhi, a discrete global grid gazetteer built using linked open data. International Journal of Digital Earth, 10(5), 490–503. doi:10.1080/17538947.2016.1229819

Leaflet plugin for Visualizing Discrete Global Grid Systems

geogrid.js

H3: Uber’s Hexagonal Hierarchical Spatial Index

See H3: Uber’s Hexagonal Hierarchical Spatial Index.