Imagery catalogues through STAC
Satellite and aerial products are indexed as STAC items with footprint, time, sensor and processing level, so analysts query by place and date and analysis runs next to the archive.
The Global Centre for Risk and Innovation (GCRI)
Geospatial information systems give every record a place: hazard grids, asset registers, boundaries and imagery brought into one frame. In this field they also carry the sharpest disclosure risks, so the work runs from coordinate reference and catalogue through to a recorded public-safe release decision.
Geospatial data infrastructure is the set of catalogues, services, standards and policies that let spatial data be found, combined and served. Here it brings hazard grids, asset registers, boundaries and imagery into one frame, with coordinate references and catalogues, and ends with a recorded decision on what is safe to publish.
The working screen behind this method: its structure, terms and states. Names are placeholders and values illustrative.
Geospatial information systems capture, store, analyse and present location-referenced data. They provide the common spatial frame for combining hazard, exposure and vulnerability information. In data and compute and methods and modelling, geospatial analysis identifies where hazards overlap critical assets and vulnerable populations. It supports location-based planning across infrastructure, health and finance. The canonical description is on the STEM Commons.
Satellite and aerial products are indexed as STAC items with footprint, time, sensor and processing level, so analysts query by place and date and analysis runs next to the archive.
Hazard layers are intersected with buildings, population grids and networks on a common equal-area grid, with the aggregation unit and denominators stated beside every count.
Before publication, sensitive layers are generalised, small counts are suppressed and combinations with other public data are reviewed; the release record names the person who decided.
Each term as this page uses it. Where a standard-setting body defines the term, the wording follows that body.
| Term | Definition |
|---|---|
| OGC API | A family of Open Geospatial Consortium web interface standards for serving features, maps, tiles and coverages. |
| Exposure overlay | Intersecting a hazard layer with population or asset layers to estimate what is exposed. |
| Public-safe release | A recorded decision on the detail at which a layer may be published without exposing sensitive sites or people. |
Surface classes an Earth-observation programme reads: ranges, deserts, glaciers, lakes and reefs, shown for Canada as an example geography for this subject.
Data from the source register feeds the methods; calibration and an independent test gate the estimate and its limits; the decision stays with the competent authority.
Fig. 01Nodes carry their type, metrics and state; connectors show what feeds what; the gates are the validation steps; the timeline is one application. Design of the method's use, not a record of a run.
Datasets and records used by geospatial information systems on this platform, with the role each plays and the label its values carry. Sources are listed in the source register.
| Data | Role | Label |
|---|---|---|
| Copernicus DEM | Terrain, drainage and inundation | MODELLED |
| OpenStreetMap | Roads, buildings and facilities | REPORTED |
| Administrative boundaries | Reporting units | OFFICIAL |
| Sentinel-2 and Landsat imagery | Land cover and change | OBSERVED |
| Gridded population | Exposure denominators | ESTIMATED |
Positional and attribute accuracy are checked against surveyed control points and reference datasets. Topology rules and metadata standards ensure consistency.
| Check | How it is done |
|---|---|
| Reference system check | Every layer's horizontal and vertical reference is declared, and transformations use EPSG definitions |
| Positional accuracy | Layers are compared with surveyed control points and the error is published with the layer |
| Topology validation | Gaps, overlaps and invalid geometries are detected before any overlay |
| Disclosure review | Published resolution and layer combinations are checked so no facility or household can be singled out |
Errors in projection, scale and data currency propagate through analysis. Aggregation to administrative units can mask local variation.
Space and Earth Observation stewards geospatial information systems for the Consortium and reviews how it is applied across platforms.
The current service level is R0: information and enquiries. An enquiry receives a reference and names the next step; applications, payments, compute allocations and registrations open only when their team, terms and review capacity exist.