SURF Platform v2.1.0 Released — Explore What's New!

SURF Platform v2.1.0 introduces improved river forcing support, automatic vertical grid generation for SURF-SHYFEM, a new compressed NetCDF4 output format, configurable data download chunks, and several bug fixes to strengthen the reliability and usability of nested coastal and regional ocean simulations.

We are pleased to announce the official release of SURF Platform v2.1.0, a maintenance and usability update for the SURF relocatable ocean modeling platform.

This release consolidates improvements for both SURF-NEMO and SURF-SHYFEM, with a particular focus on preprocessing robustness, river forcing support, configuration flexibility, and more efficient handling of model inputs and outputs.

For SURF-NEMO v2.1.0, this version was originally prepared in September 2025 as an internal and unofficial release, and is now officially published together with the updated SURF-NEMO documentation. The source code is unchanged with respect to the September 2025 version.

The SURF-NEMO component adds support for river boundary conditions, allowing configurations to include river discharge forcing directly within the workflow. This is particularly relevant for shelf and coastal applications where freshwater input can influence stratification, circulation, and nearshore dynamics.

SURF-NEMO v2.1.0 also fixes a preprocessing issue affecting domains defined with negative longitudes, such as western-hemisphere regions. These domains are now correctly detected and processed.

For SURF-SHYFEM v2.1.0, the release introduces automatic vertical grid generation. The levels parameter is no longer required in the Base configuration: users can now either provide an explicit list of z-levels or rely on automatic generation through a hyperbolic tangent stretching scheme, similar to the NEMO 5.0 approach, with finer resolution near the surface and coarser spacing toward the bottom.

The SURF-SHYFEM output workflow has also been redesigned. Simulation results are now saved as a single compressed NetCDF4 file, surf.nc, replacing the previous separated surf.ous.nc and surf.nos.nc files. Physical variables are provided at the node positions of the unstructured grid, and the compression level can be controlled through the Expert configuration.

Additional SURF-SHYFEM improvements include a configurable simulation start time, user control of bottom heat absorption, configurable river data paths, and chunked downloads for CMEMS and ECMWF forcing datasets. The download workflow now supports automatic retries with progressively smaller chunk sizes in case of failure, improving robustness when retrieving large atmospheric and ocean forcing datasets.

The release also improves open-boundary node extraction and ordering during grid generation, skips SSH downloads for ocean initialization because SHYFEM-MPI is now initialized from rest for sea surface height, and fixes a time-centering issue affecting daily-averaged CMEMS forcing products that previously caused a 12-hour phase shift.

Finally, SURF-SHYFEM v2.1.0 updates the Mediterranean Sea reanalysis product identifiers to match the current CMEMS data store catalog naming convention, ensuring compatibility with the latest data access infrastructure.

We encourage users to upgrade to SURF Platform v2.1.0 and explore the updated release notes for both SURF-NEMO and SURF-SHYFEM.