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Add link to version release in PolyTEOS10_bsq Kernel blog post #186

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erikvansebille merged 2 commits into from
Aug 7, 2025
Merged

Add link to version release in PolyTEOS10_bsq Kernel blog post #186

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Add link to version release
VeckoTheGecko Aug 7, 2025
b74db45
Adding another article that's probably impacted by the polyTEOS10 bug
erikvansebille Aug 7, 2025
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3 changes: 2 additions & 1 deletion src/posts/polyteos10-kernel/index.md
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Expand Up @@ -12,7 +12,7 @@ summary: 'An issue with the `PolyTEOS10_bsq` kernel has been identified, where i
In recent days we’ve come across a bug in an application kernel of `parcels`. The `PolyTEOS10_bsq` kernel is used to calculate the density of seawater from the temperature and salinity fields. The kernel is based on equation (13) from
[Roquet et al. (2014)](https://doi.org/10.1016/j.ocemod.2015.04.002) where the density $\rho$ is determined from the summation of a vertical reference profile $r_0$ and a residual function or density anomaly $r$. That is, $\rho(S,T,z) = r_0(z) + r(S,T,z)$.

Up until the fix in [PR #2133](https://github.com/OceanParcels/Parcels/pull/2133), the kernel only computed the density anomaly $r$, and did not include the vertical reference profile. At the ocean surface this isn’t a problem, as $r_0(z=0) = 0$ and so the computed density was correct. However, $r_0(z)>0$ below the ocean surface, and at relatively deep depths, this value can be significant. For example, at 100 m depth this value is 0.46443 kg/m$^3$ and at 500 m depth this value is 2.31175 kg/m$^3$, see the figure below.
Up until the fix in [v3.1.3](https://github.com/OceanParcels/Parcels/releases/tag/v3.1.3) (see [PR #2133](https://github.com/OceanParcels/Parcels/pull/2133)), the kernel only computed the density anomaly $r$, and did not include the vertical reference profile. At the ocean surface this isn’t a problem, as $r_0(z=0) = 0$ and so the computed density was correct. However, $r_0(z)>0$ below the ocean surface, and at relatively deep depths, this value can be significant. For example, at 100 m depth this value is 0.46443 kg/m$^3$ and at 500 m depth this value is 2.31175 kg/m$^3$, see the figure below.

![Vertical reference profile as a function of depth](/posts/polyteos10-kernel/depth_vs_r0.png)

Expand All @@ -27,3 +27,4 @@ Below we’ve compiled a list of several papers that may be impacted, but we urg
- [Modelling submerged biofouled microplastics and their vertical trajectories, _Biogeosciences_ (2022)](https://doi.org/10.5194/bg-19-2211-2022)
- [Influence of Particle Size and Fragmentation on Large-Scale Microplastic Transport in the Mediterranean Sea, _Environmental Science & Technology_ (2022)](https://doi.org/10.1021/acs.est.2c03363)
- [Global Modeled Sinking Characteristics of Biofouled Microplastic, _JGR Oceans_ (2021)](https://doi.org/10.1029/2020JC017098)
- [Resolution dependency of sinking Lagrangian particles in ocean general circulation models, _PLOS One_ (2020)](https://doi.org/10.1371/journal.pone.0238650)