From a7db93edf94bbd457b64c1f0d4693201aa2b3d4e Mon Sep 17 00:00:00 2001 From: Vecko <36369090+VeckoTheGecko@users.noreply.github.com> Date: Thu, 7 Aug 2025 10:42:44 +0200 Subject: [PATCH 1/2] Add link to version release --- src/posts/polyteos10-kernel/index.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/posts/polyteos10-kernel/index.md b/src/posts/polyteos10-kernel/index.md index f83e91c..b003fe5 100644 --- a/src/posts/polyteos10-kernel/index.md +++ b/src/posts/polyteos10-kernel/index.md @@ -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) From b74db45b4b7ba1db8edd4735b49ea6834f9c9386 Mon Sep 17 00:00:00 2001 From: Erik van Sebille Date: Thu, 7 Aug 2025 11:15:32 +0200 Subject: [PATCH 2/2] Adding another article that's probably impacted by the polyTEOS10 bug --- src/posts/polyteos10-kernel/index.md | 1 + 1 file changed, 1 insertion(+) diff --git a/src/posts/polyteos10-kernel/index.md b/src/posts/polyteos10-kernel/index.md index b003fe5..bd2398a 100644 --- a/src/posts/polyteos10-kernel/index.md +++ b/src/posts/polyteos10-kernel/index.md @@ -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)