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Instrument · calibration
Node · envelope, buffer, quality
Site · outbox
governed data store · inbox, governed data
Consumer · product
4.56 °CGNSS ±1 µs · u ±0.15
flags none · aws-07
NOAA ISD · U.S. Government work
USGS NWIS · U.S. Government work
ECCC hydrometric · ECCC end-use licence
NEON · CC0 1.0
Argo floats · CC BY 4.0
AmeriFlux · CC BY 4.0
WRI power plants · CC BY 4.0
Sensor.Community · ODbL 1.0 · research only
INTERMAGNET · CC BY-NC 4.0 · research only
PSMSL tide gauges · Free with citation · research only
Derived product · 2 sources, 1 attribution line
Research · open
Commercial API · open
Enterprise · open
Government · open
Open release · open
NOAA ISD
ECCC hydrometric
USGS NWIS
Argo floats
P1 · gridded field · v1
P2 · index · v1
P3 · nowcast · v1
P4 · QC report · v1
P5 · composite · v1
P6 · index of indices · v1
API
Map
Export
Alerts
Canada
United States of America
Germany
Japan
Australia
Brazil
refused at the boundary
Sites
Governed products
API
Events
Maps
Export
Open release
Inbound management path · none
Alberta · 146 stations
Intro. Instrument · calibration; Node · envelope, buffer, quality; Site · outbox; governed data store · inbox, governed data; Consumer · product; 4.56 °CGNSS ±1 µs · u ±0.15flags none · aws-07
Data · Explainer
Every value leaves the instrument with its unit, time quality, quality flags and provenance, and keeps them all the way to your product. The licence of every source is carried through to every product, corrections flow downstream without deleting history, and residency is fixed by contract.
01 · Pipeline
An instrument measures with its identity and calibration. The node wraps the value in an observation envelope with time quality, buffers it when the link drops, measures quality and uncertainty, and publishes through a transactional outbox, delivered at least once. The inbox upstream deduplicates by event id, so a value lands once however often it is sent. Inject a fault and follow the packet.
Fault
instrument → node · calibration-recordnode → node · observationnode → node · event-envelopenode → node · quality-flagnode → site · event-envelopesite → data-store · observationdata-store → api-consumer · product-manifest{ "observationUni": "obs-1001", "systemUni": "aws-07", "observedProperty": "air_temperature", "phenomenonTime": "2026-10-28T05:14:18Z", "resultTime": "2026-10-28T05:14:18Z", "result": 4.56, "unit": "Cel", "uncertainty": { "u": 0.15, "k": 2 }, "qualityFlags": [], "timeQuality": { "source": "GNSS", "offsetBound": "±1 µs" }, "evidenceRefs": [ "cal-aws-07-r4" ], "schemaVersion": "1.0" } 02 · Licensing
A derived product carries the union of its inputs’ obligations and the intersection of their permissions. One non-commercial input closes the commercial tiers; one share-alike database fixes the licence of what is built from it; every attribution travels. Choose the sources a product draws on and see where it may go.
03 · Corrections
When a source corrects a value, the dependency graph is walked: every product that used it is marked stale, only those are recomputed, each gets a new version that names what it supersedes, and subscribers are told. Nothing is deleted; the old version stays readable with its correction state. Pick a source to correct.
Correct
source-steward → data-store · correction-noticedata-store → data-store · correction-noticedata-store → data-store · evidence-recorddata-store → api-consumer · product-manifest04 · Residency
The compiler evaluates data rights and locality before it places anything, and it is compute-to-data aware: when rows may not leave a region, the work travels to the data and only the permitted result comes back. Set the region, the requester and the request.
Data region
Requester in
Request
05 · Exchange
Governed products reach people and applications through versioned APIs, events, maps and exports. None of them opens an inbound management path into a site: requests stop at the governed product, and a map paint is bound to its product by a grounding receipt. Open release is one more channel, open only when the licence allows it.
Channel
06 · Requests
A request names a property, an area and a time window. The size of the answer follows from the stations inside the area, the window and the reporting interval; each observation comes back with its quality and provenance attached. The stations counted here are real surface weather stations.
Area
Interval
Form
GET /v1.1/Observations ?$filter=st_within(FeatureOfInterest/feature, geography'POLYGON((-120 49,-110 49,-110 60,-120 60,-120 49))') and ObservedProperty/name eq 'air_temperature' and phenomenonTime ge 2026-10-27T15:00:00Z and phenomenonTime lt 2026-10-28T05:00:00Z &$select=phenomenonTime,result,resultQuality &$top=2044
Every value leaves the instrument with its unit, time quality, quality flags and provenance, and keeps them all the way to your product. The licence of every source is carried through to every product, corrections flow downstream without deleting history, and residency is fixed by contract.
An instrument measures with its identity and calibration. The node wraps the value in an observation envelope with time quality, buffers it when the link drops, measures quality and uncertainty, and publishes through a transactional outbox, delivered at least once. The inbox upstream deduplicates by event id, so a value lands once however often it is sent. Inject a fault and follow the packet.
A derived product carries the union of its inputs’ obligations and the intersection of their permissions. One non-commercial input closes the commercial tiers; one share-alike database fixes the licence of what is built from it; every attribution travels. Choose the sources a product draws on and see where it may go.
When a source corrects a value, the dependency graph is walked: every product that used it is marked stale, only those are recomputed, each gets a new version that names what it supersedes, and subscribers are told. Nothing is deleted; the old version stays readable with its correction state. Pick a source to correct.
The compiler evaluates data rights and locality before it places anything, and it is compute-to-data aware: when rows may not leave a region, the work travels to the data and only the permitted result comes back. Set the region, the requester and the request.
Governed products reach people and applications through versioned APIs, events, maps and exports. None of them opens an inbound management path into a site: requests stop at the governed product, and a map paint is bound to its product by a grounding receipt. Open release is one more channel, open only when the licence allows it.
A request names a property, an area and a time window. The size of the answer follows from the stations inside the area, the window and the reporting interval; each observation comes back with its quality and provenance attached. The stations counted here are real surface weather stations.
The smallest unit is one station’s record: values with their time, place, quality and provenance. A site merges its instruments into one record; a cluster keeps a shared archive; a region publishes a catalogue; the global layer federates catalogues so a user finds data without knowing who holds it. The same principles apply at every level: findable, accessible, interoperable and reusable, for people and for machines.
A value moves from raw counts to calibrated units, through quality control, into derived products and finally publication. At each step the lineage is recorded in the terms of the W3C provenance model: the entity produced, the activity that produced it and the agent responsible, including the software version. When an upstream value is corrected, the lineage finds every product downstream that must be remade.
Sources W3C, PROV-O: The PROV Ontology
Long-term keeping is a discipline of its own. The reference model for an open archival information system divides it into ingest, archival storage, data management, preservation planning and access. Fixity checks prove that stored bytes have not changed, copies sit in separate places, and formats are watched so the record can be migrated before the software that reads it disappears.
Sources ISO 14721 and CCSDS 650.0-M, Reference Model for an Open Archival Information System (OAIS)
Every feed has an expected cadence. A late or missing delivery is flagged, checksums confirm that what arrived is what was sent, and operators see exceptions rather than every file. A stale feed opens one ticket carrying the source’s last good timestamp. The data quality model names currentness alongside accuracy and completeness, so freshness is measured, not assumed.
Sources ISO/IEC 25012, Data quality model
A dataset is planned before it is collected: who owns it, which licence it carries, how long it is kept. It is then collected, described with catalogue metadata, preserved and reused. A standard catalogue vocabulary lets the same description serve a portal, a search engine and another archive, so a dataset stays discoverable long after the project that made it has ended.
Under which licence, and does it allow commercial use and redistribution? Can each value be traced to its source and processing? Where is it stored, and under which law? Is it in open formats a different tool can read? Can a full copy leave with you? An open licence is one that lets anyone use, change and share the data, subject at most to attribution and share-alike terms.
Sources Open Knowledge Foundation, The Open Definition, version 2.1