v4 preview release#291
Draft
erikvansebille wants to merge 1 commit into
Draft
Conversation
erikvansebille
commented
Jun 25, 2026
|
|
||
| See the full migration guide from Parcels v3 to v4 [here](https://docs.parcels-code.org/en/main/user_guide/v4-migration.html). | ||
|
|
||
| Note that Parcels v4-preview is not a stable release yet, and we are still working on improving the performance of the framework and adding new features. We welcome feedback from the community, and encourage users to try out the new version and [report any issues or suggestions](https://github.com/Parcels-Code/parcels/issues). |
Member
Author
There was a problem hiding this comment.
TODO: Add link to new performance tutorial here
erikvansebille
commented
Jun 25, 2026
|
|
||
| Note that Parcels v4-preview is not a stable release yet, and we are still working on improving the performance of the framework and adding new features. We welcome feedback from the community, and encourage users to try out the new version and [report any issues or suggestions](https://github.com/Parcels-Code/parcels/issues). | ||
|
|
||
| Funded by the [WarmWorld ELPHE project](https://www.geomar.de/en/research/ongoing-projects/project-details/prj/376612?cHash=449a07d057ea0d890287bd2b8ca26e8b) funded by the German Federal Ministry for Research, Technology and Space (BMFTR) and the [NWO Vici project “Tracing Marine Macroplastics by Unraveling the Ocean’s Multiscale Transport Processes”](https://www.nwo.nl/en/projects/vic222025), the development of Parcels v4 started in September 2025 and was a collaboration between the [GEOMAR Helmholtz Centre for Ocean Research Kiel](https://www.geomar.de/en/), [FluidNumerics](https://www.fluidnumerics.com/) and the [University of Utrecht](https://www.uu.nl/en) in the Netherlands. The development was led by Nick Hodgskin, Joe Schoonover and Erik van Sebille, with contributions from many others, including Willi Rath, Daniel Lizarbe, and Michael Denes. |
Member
Author
There was a problem hiding this comment.
Anyone else we missed?
Member
Author
|
Hi @VeckoTheGecko and @fluidnumericsJoe, I have drafted a blog post for the release of Parcels v4-preview. No real rush yet, but could you have a look whether you agree with this text, and where you think it can be further improved? |
7 tasks
erikvansebille
commented
Jun 25, 2026
| @@ -0,0 +1,31 @@ | |||
| --- | |||
| title: 'Parcels v4.0-preview is available! 🚀' | |||
| date: '2026-08-01' | |||
Member
Author
There was a problem hiding this comment.
This is a placeholder for now; will need to adapt this to the actual release date
VeckoTheGecko
requested changes
Jun 25, 2026
VeckoTheGecko
left a comment
VeckoTheGecko
left a comment
Contributor
There was a problem hiding this comment.
Thanks for putting this together @erikvansebille ! Here's some preliminary feedback - I'm happy to review again closer to release.
Contributor
There was a problem hiding this comment.
We should refer to this version as v4.0 instead of v4-preview or v4.0-preview. We should also capitalise package names (Xarray, Python, Zarr, Dask etc.)
|
|
||
| We are very excited to announce that Parcels v4-preview is now available for performing Lagrangian simulations in hydrodynamic flows. Parcels v4 is a complete redesign of the [Parcels code](https://parcels-code.org) and is designed to be more flexible and extensible than previous versions. | ||
|
|
||
| Parcels v4 is pure python code, so that it can leverage the full power of the [Pangeo ecosystem](https://pangeo.io/) of geoscience python tools such as xarray, dask and zarr. Particle advection and interpolation are now vectorised operations, which improves performance and makes [particle-particle interactions](https://docs.parcels-code.org/en/main/user_guide/examples/tutorial_interaction.html) easier to implement. |
Contributor
There was a problem hiding this comment.
Suggested change
| Parcels v4 is pure python code, so that it can leverage the full power of the [Pangeo ecosystem](https://pangeo.io/) of geoscience python tools such as xarray, dask and zarr. Particle advection and interpolation are now vectorised operations, which improves performance and makes [particle-particle interactions](https://docs.parcels-code.org/en/main/user_guide/examples/tutorial_interaction.html) easier to implement. | |
| With this release - Parcels is a pure Python package that leverages the full power of the [Pangeo ecosystem](https://pangeo.io/) of geoscience python tools such as xarray, dask and zarr. Particle advection and interpolation are now vectorised operations, which improves performance and makes [particle-particle interactions](https://docs.parcels-code.org/en/main/user_guide/examples/tutorial_interaction.html) easier to implement. |
|
|
||
| Parcels v4 is pure python code, so that it can leverage the full power of the [Pangeo ecosystem](https://pangeo.io/) of geoscience python tools such as xarray, dask and zarr. Particle advection and interpolation are now vectorised operations, which improves performance and makes [particle-particle interactions](https://docs.parcels-code.org/en/main/user_guide/examples/tutorial_interaction.html) easier to implement. | ||
|
|
||
| Key improvements of Parcels v4 are |
Contributor
There was a problem hiding this comment.
Suggested change
| Key improvements of Parcels v4 are | |
| Key improvements include: |
|
|
||
| See the full migration guide from Parcels v3 to v4 [here](https://docs.parcels-code.org/en/main/user_guide/v4-migration.html). | ||
|
|
||
| Note that Parcels v4-preview is not a stable release yet, and we are still working on improving the performance of the framework and adding new features. We welcome feedback from the community, and encourage users to try out the new version and [report any issues or suggestions](https://github.com/Parcels-Code/parcels/issues). |
Contributor
There was a problem hiding this comment.
Suggested change
| Note that Parcels v4-preview is not a stable release yet, and we are still working on improving the performance of the framework and adding new features. We welcome feedback from the community, and encourage users to try out the new version and [report any issues or suggestions](https://github.com/Parcels-Code/parcels/issues). | |
| Note that Parcels v4.0 is an early release to gather user feedback and should not be considered stable. We welcome feedback from the community, and encourage users to try out the new version and [report any issues or suggestions](https://github.com/Parcels-Code/parcels/issues). Once incorporating this feedback, improving performance, and implementing a few outstanding features, we aim to release a stable version of Parcels. |
| 3. Support for [user-defined interpolators](https://docs.parcels-code.org/en/main/user_guide/examples/explanation_interpolation.html). | ||
| 4. More robust and flexible support for [nested grids](https://docs.parcels-code.org/en/main/user_guide/examples/tutorial_nestedgrids.html). | ||
|
|
||
| We have also changed the [output format to `parquet`](https://docs.parcels-code.org/en/main/getting_started/tutorial_output.html#reading-the-output-file), which is a tabular format and therefore more efficient and flexible for storing large datasets. |
Contributor
There was a problem hiding this comment.
Suggested change
| We have also changed the [output format to `parquet`](https://docs.parcels-code.org/en/main/getting_started/tutorial_output.html#reading-the-output-file), which is a tabular format and therefore more efficient and flexible for storing large datasets. | |
| We have also changed the [output format to `parquet`](https://docs.parcels-code.org/en/main/getting_started/tutorial_output.html#reading-the-output-file), which is a tabular format more suited for writing and reading trajectory data. |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
This PR gets parcels-code.org ready for the release of Parcels v4-preview. Most importantly, it adds a blog post detailing the new v4-preview
Note that we will also need to make some changes to the docs-side; these are tracked in Parcels-code/Parcels#2702