Universal Geospatial Data Exchange via Global Hierarchical Coordinates

Geoffrey Dutton

Spatial Effects
20 Payson Road
Belmont, Massachussets

Email: dutton@spatial-effects.com

Link to full paper

Hierarchical coordinates can be considered as leaf node identifiers in quadtrees or nonary trees, numbered canonically. To achieve global coverage, the most straightforward approach is to develop triangular tessellations of a platonic solid fitted to the earth (or other spheroidal body). In practice, octahedra and icosahedra seem to be the best choices for a base solid, and triangular quaternary breakdown of their faces also tends to be preferred. The hierarchical coordinated system described is based on the octahedral quaternary triangular mesh (O-QTM). Its form, topology, geometry, numbering system, nesting and areal variations are summarized. Other hierarchical global grids can be designed for geocoding and data exhange purposes, but will tend to have similar properties, advantages and disadvantages as QTM.

Geospatial data interchange is then addressed. To overcome limitations and incompatibilities of local coordinate systems and spatial identifiers, QTM's use is proposed for encoding and notating positional data. Widespread adoption of the such a method will yield a more efficient, elegant and reliable geospatial data infrastructure, avoid common errors and uncertainties, and save billions in geodata (re)processing costs. The approach can be made completely transparent to many users, promote distributed spatial data libraries and applications, and conserve network bandwidth during data transmission.