Overview
ISO 19170-1:2021 - Geographic information - Discrete Global Grid Systems Specifications - Part 1 defines a normative core for Discrete Global Grid Systems (DGGS) and an Equal-Area Earth Reference System (EAERS). The standard specifies a reference system (RS) that uses zonal identifiers with structured geometry, a set of common spatio‑temporal data classes, and core functions for quantization, topological query and interoperation. It includes informative annexes on theory and background to guide implementation.
Key technical topics and requirements
- DGGS Core RS using zonal identifiers
- Defines an RS where the world is partitioned into zones created by recursive tessellation.
- Each zone has a unique zonal identifier and an associated representative position in a base Coordinate Reference System (CRS).
- Common spatio‑temporal classes
- Data models for geometry, topology, identifiers and RSs using identifiers consistent with ISO 19111 (spatio‑temporal CRS pattern).
- Scope constrained to spatial classes invariant through time and temporal classes invariant across space.
- Core functions and operations
- Quantization functions (mapping continuous coordinates into DGGS zones), topological query functions (neighbourhoods, adjacency), and interoperation/import‑export capabilities.
- Equal‑Area Earth RS (EAERS)
- A specialization of the DGGS Core: base unit polyhedron, hierarchical global grids with equal‑area zones, and unique identifiers located in a geodetic (typically geographic) CRS.
- Conformance and testability
- Packages and conformance classes are specified; an abstract test suite is provided (normative).
- Informative material
- Annexes include EAERS theory, DGGS background and temporal modelling context.
Practical applications and users
ISO 19170-1 is designed for organizations and practitioners who need efficient global spatial indexing, analysis and data interchange:
- GIS and spatial data architects implementing DGGS for global tiling and spatial indexing
- Earth observation, remote sensing and geospatial analytics platforms requiring consistent global grids
- Environmental and socio‑economic modelling where interoperable, multi‑resolution storage is needed
- Developers of spatial APIs, data services and spatial databases seeking standard DGGS operations (quantization, topological queries, import/export)
- Standards bodies and implementers collaborating with the OGC and ISO/TC 211 for interoperable geospatial systems
Related standards and future work
- Aligned with ISO 19111 (CRS pattern) and informed by ISO spatial/temporal models (ISO 19107, ISO 19112, ISO 19108).
- Developed in close collaboration with the Open Geospatial Consortium (OGC).
- Future ISO 19170 parts planned: 3D/equal‑volume RS, spatio‑temporal RS, axis‑aligned RS, a DGGS‑API and a registry for DGGS definitions.
Keywords: ISO 19170-1:2021, Discrete Global Grid Systems, DGGS, Equal-Area Earth Reference System, zonal identifiers, spatio-temporal, quantization, topological query, geodetic CRS.