# OGC Standard Working Group - GeoZarr

This page collects the meeting minutes for the OGC GeoZarr SWG (:link: [GitHub](https://github.com/zarr-developers/geozarr-spec)).

:calendar: **Next**: **April 1, 2026** (:warning: **first Wednesday of each month**)
:watch: **UTC**: 4:00PM | **EDT**: 11:00AM | **PDT**: 8:00AM | **CET**: 5:00PM | [[more timezones](https://www.timeanddate.com/worldclock/fixedtime.html?msg=GeoZarr+SWG&iso=20260401T11&p1=746&ah=1)]
:link: [Join the meeting now](https://meet.google.com/jth-rstn-fwb) (or [by phone](https://tel.meet/jth-rstn-fwb?pin=9845739928663))
:mega: Follow announcements by [joining Agora](https://agora.ogc.org/c/overview-716766/)

If you have questions, please email max ([e-mail])

# April 1st, 2026

## Attendees

- Max Jones
- Wietze Suijker
- Chris Little
- Tom Nicholas
- Kathi Schleidt
- Patrick Van Laake
- Ethan Davis

## Agenda

1. Welcome & Roll Call (5 min)
2. Review March Action Items (10 min)
- Max J. — OGC IP clause meeting with Scott/Greg outcome - deferred, will organize before the next meeting
- Max J. — Implementation criteria PR status - opened in https://github.com/zarr-developers/geozarr-spec/pull/128, needs reviewers
- Emmanuel — Implementation matrix disclaimers (e.g., fixed-scale offset in openlayers) - deferred, Max will open PR and ping Emmanuel
- Patrick — R library details; Julia community outreach
- Tyler — HackMD admin status - done
- Validator per-convention reporting update - done
3. CF Alignment Update (10 min)
- CF Governance Panel met March 19 — what was the outcome?
- Dave Blodgett's Zarr-focused proposal — any progress?
- Next steps for GeoZarr/CF integration path
4. Implementation Readiness (10 min)
- Review implementation criteria (if PR was opened)
- Updated matrix: GDAL ([ready on master](https://github.com/OSGeo/gdal), [3.13 release planned for May 4](https://github.com/OSGeo/gdal/milestone/65), OpenLayers, EOPF, rioxarray, QGIS
- New implementations or expressions of interest?
- Gap assessment: are we on track for 3+ independent implementations?
5. Multiscales & Web Tile Rendering (5 min)
- OpenLayers, others disattisfied by needing to parse shard/chunk sizes codecs
- PR and proofs of concepts will be forthcoming this week
6. V1 Release Candidate Timeline (5 min)
- May 2026 target — still realistic?
- Remaining blockers: conformance classes, test datasets, JSON Schema stability
- Adjust timeline if needed
7. Governance & Hosting (5 min)
- OGC IP clause resolution
- GitHub org decision ([#126](https://github.com/zarr-developers/geozarr-spec/issues/126))
- Co-chair nomination — any volunteers?
8. Any Other Business / Next Meeting (5 min)

# March 4th, 2026

## Attendees
- Max Jones [Development Seed]
- Tyler Erickson [VorGeo, Radiant Earth]
- Patrick
- Gui Castelao [NREL]
- Max Guntrum
- Colby Fisher
- Ethan Davis
- Emmanuel Mathot
- Matthias Mohr
- Wietze Suijker

## Agenda

1. Welcome & Roll Call (5 min)
2. Review February Action Items (10 min)
- **Updates from SWG lead**:
- GitHub issues created for necessary tasks before OGC submission
- Created website with FAQ and roadmap tracking - https://geozarr.org
- removed wiki to have one landing page
- [this PR](https://github.com/zarr-developers/geozarr-spec/pull/124) updates the links in the repo
- Created a GeoZarr online validator - https://inspect.geozarr.org powered by [geozarr-toolkit](https://github.com/zarr-developers/geozarr-toolkit)
- **Updates to be requested**:
- Ethan, Patrick, or Gui - Follow-ups from the CF alignment meeting
- Patrick Van Laake — CRS guidance issue in spatial convention repo
- Wietze - where should people look to get started with QGIS plugin?
- search "GeoZarr" in the QGIS plugin manager. Full sharding support requires GDAL 3.13 (mid-2026, or [build from master](https://github.com/OSGeo/gdal))
- 1. Plugin Manager > search "GeoZarr" > Install
- 2. Browser panel > STAC > New Connection:
https://api.explorer.eopf.copernicus.eu/stac
- 3. Right-click any Sentinel-2 item > Load GeoZarr
- **Open call for announcements**
3. Implementation Updates (10 min)
- Progress toward 3+ implementations (Candidate maturity threshold)
- Known implementations: eopf data-model, zarr-cm, rioxarray, GDAL, OpenLayers, TiTiler
- Request updates from implementers
4. Governance & Hosting (5 min)
- **Reminder** - You must sign https://agora.ogc.org/c/discover-standards-working-groups-swg/geozarr-swg to be a voting member
- **OGC contribution statement** — agreement on [#125](https://github.com/zarr-developers/geozarr-spec/pull/125)
- Request: 1-2 more admins for https://hackmd.io/team/geozarr/ (bus/lottery factor reduction)
- Please comment on [Discussion: final GitHub hosting location for GeoZarr materials](https://github.com/zarr-developers/geozarr-spec/issues/126)
5. V1 Roadmap Check-in (15 min)
- Milestone 1 (Release Candidate) status
- Chunking recommendations?
- Minimal GeoZarr requirements?
- Convention finalization progress
- Conformance classes
- JSON Schema stability
- Test dataset suite
- Summer 2026 OAB review timeline — are we on track?
6. Any Other Business / Next Meeting (5 min)
- [get involved guide](https://geozarr.org/get-involved.html)

# February 4th, 2026

## Attendees

- Emmanuel Mathot [DS]
- Konstantin Ntokas [Brockmann Consult]
- Gui Castelao (@castelao)
- Max Jones [DS]
- Atanas Balevsky
- kathi schleidt
- Christophe Noël
- Patrick Van Laake
- Chris Little
- Wietze Suijker
- Len Strnad
- Tom Nicholas

## Agenda

### 1. Welcome & Roll Call (5 min)

### 2. Review January Action Items (10 min)

| Action Item | Owner | Status |
|-------------|-------|--------|
| Draft strawman proposal for CF-on-Zarr conventions | Max | |
| Update GeoZarr examples repo with real-world use cases | Max | |
| Create GeoZarr issue to discuss consistent versioning | Max | |
| Share QGIS plugin for feedback in CNG Slack | Wietze | |
| Email David Hassel & Jonathan Gregory re: CF-GeoZarr alignment | | |
| Email UK Met Office re: CF-GeoZarr support | | |
| Compile and upload old Fathom notes to Agora | Max | |
| Merge GeoZarr PRs | Max | |

### 3. Strawman Proposal: v1 Project Board & Issue Tracking (20 min)

Presenting a strawman proposal for organizing GeoZarr v1 release work.

**Materials:** `geozarr-spec/issues/PROJECT_BOARD.md`

**Discussion points:**
- Proposed milestones: v1-rc → v1-oab → v1-vote → post-v1
- 15 draft issues covering spec, docs, testing, interoperability
- Simplified labels (8 total)
- Zarr Conventions Framework maturity levels (Candidate = 3+ implementations)

**Questions for the group:**
- Are the proposed milestones appropriate?
- Are any issues missing or unnecessary?
- What target dates should we set?
- Who can own specific issues?

### 4. Convention Adoption Updates (10 min)

- **EOPF Explorer V1** - Status update (was due end of January)
- **GDAL** - Progress on read-only Multiscales/GeoproJ support
- **QGIS Plugin** - Demo or status update from Wietze
- **OpenLayers** - Multiscales PR status
- **Other adopters**

### 5. CF-on-Zarr Alignment (10 min)

- Status of strawman proposal for formalizing CF-on-Zarr patterns
- Feedback from CF community contacts
- Path forward

### 6. Governance Updates (5 min)

- **Co-chair status** - Term ended in February; any nominations?
- **Zarr Governance Council** - Update on project boundaries clarification
- **Communication channels** - Agora and CNG Slack adoption

### 7. Next Steps & Action Items (5 min)

### 8. Any Other Business
- Confirm Max Jones’s official mandate as GeoZarr SWG Co-Chair.
- Ask volunteer willing to support as co-chair alongside Max Jones
- Emmanuel updates:
- Official opening of the EOPF Explorer platform at https://explorer.eopf.copernicus.eu/. We have a [dedicated page for GeoZarr](https://explorer.eopf.copernicus.eu/datamodel/)
- first PR on rioxarray to accept more conventions: https://github.com/corteva/rioxarray/pull/899
spatial and projection conventions will follow in https://github.com/corteva/rioxarray/pull/900

### Parking lot (technical discussions)

* How are the existing implementations identifying conventions in practice (UUID vs name, etc.)?

# January 7th, 2026

### Attendees

- Ryan Abernathey (@rabernat)
- Emmanuel Mathot (@emmanuelmathot)
- Wietze Suijker
- Tom Nicholas
- Tyler Erickson (@tylere)
- Chris Little
- Max Jones
- Colby Fisher
-

### Agenda

* Roundrobin updates
* SWG chairs - nominate yourself by responding to https://agora.ogc.org/c/overview-716766/call-for-nominations-geozarr-swg-co-chair-baa05a69-c79b-46ce-8657-07096b87103b
* Versioning zarr conventions ([issue #102](https://github.com/zarr-developers/geozarr-spec/issues/102)) - please comment on https://github.com/zarr-developers/geozarr-spec/issues/102

### Notes

* Roundrobin updates
* Ryan
* Governance update from SC coming soon
* Post blog post after we get adopter
* Emmanuel
* Openlayers has examples working for an implementation
* Delivering EOPF Zarr Viz V1 at the end of the month
* Played with some Zarr layers from carbonplan
* Titiler is compliant; gdal working on it
* Opened a PR for rioxarray support for Zarr conventions: https://github.com/corteva/rioxarray/pull/883
* Chris
* Lots of met offices are moving into the cloud
* Interested in CF convention part
* need to involve more CF and met people
* approach David Hassel and Jonathon Gregor
* Max
* FYI about co-chair activities - Max will be compiling old fathom notes to link from the Agora site with summaries also on GitHub, as well as proposing some updates to the GH repository. PRs will be merged on Friday, so please submit any comments before then
* Zarr conventions spec (enabling the conventions that are pillars for GeoZarr) was released in December - https://zenodo.org/records/17884186
* hosting weekly zarr conventions coworking session - https://zarr.dev/community-calls/

* Wietze
* experimental Geozarr support in QGIS stac plugin
* [DEMO screen recording](https://github.com/user-attachments/assets/d60b7823-1307-4809-903d-5d41cc723ce4)
* [PR](https://github.com/stac-utils/qgis-stac-plugin/pull/283)