Mixed layer depth in the PMIP4 <i>midHolocene</i> simulations: comparison to proxy data in North Atlantic deep convection regions

Wu, Xiner; de Vernal, Anne; Myers, Paul G.

doi:10.5194/cp-22-1609-2026

Articles | Volume 22, issue 9

https://doi.org/10.5194/cp-22-1609-2026

© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.

https://doi.org/10.5194/cp-22-1609-2026

© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 22, issue 9

Research article

|

02 Sep 2026

Research article |

| 02 Sep 2026

Mixed layer depth in the PMIP4 midHolocene simulations: comparison to proxy data in North Atlantic deep convection regions

Xiner Wu, Anne de Vernal, and Paul G. Myers

Supplement

https://doi.org/10.5194/cp-22-1609-2026-supplement

Data sets

PalMod2 MPI-M MPI-ESM1-2-CR Transient Simulations of the Last Deglaciation with prescribed ice sheets from ICE-6G reconstructions (r1i1p1f1) Uwe Mikolajewicz et al. https://doi.org/10.26050/WDCC/PMMXMCRTDIP111

PalMod2 MPI-M MPI-ESM1-2-CR Transient Simulations of the Last Deglaciation with prescribed ice sheets from ICE-6G reconstructions (r1i1p2f2) Uwe Mikolajewicz et al. https://doi.org/10.26050/WDCC/PMMXMCRTDIP122

PalMod2 MPI-M MPI-ESM1-2-CR Transient Simulations of the Last Deglaciation with prescribed ice sheets from ICE-6G reconstructions (r1i1p3f2) Uwe Mikolajewicz et al. https://doi.org/10.26050/WDCC/PMMXMCRTDIP132

PalMod2 MPI-M MPI-ESM1-2-CR Transient Simulations of the Last Deglaciation with prescribed ice sheets from GLAC-1D reconstructions (r1i1p1f1) Uwe Mikolajewicz et al. https://doi.org/10.26050/WDCC/PMMXMCRTDGP111

PalMod2 MPI-M MPI-ESM1-2-CR Transient Simulations of the Last Deglaciation with prescribed ice sheets from GLAC-1D reconstructions (r1i1p2f2) Uwe Mikolajewicz et al. https://doi.org/10.26050/WDCC/PMMXMCRTDGP122

PalMod2 MPI-M MPI-ESM1-2-CR Transient Simulations of the Last Deglaciation with prescribed ice sheets from GLAC-1D reconstructions (r1i1p3f2) Uwe Mikolajewicz et al. https://doi.org/10.26050/WDCC/PMMXMCRTDGP132

A multi-model assessment of the early last deglaciation (PMIP4 LDv1) Brooke Snoll et al. https://doi.org/10.5518/1398

(Table S2) Percentages of common modern dinoflagellate cyst taxa in surface sediments of the Northern Hemisphere and corresponding environmental parameters Anne de Vernal et al. https://doi.org/10.1594/PANGAEA.908494

Mixed layer depth values for the n = 1968 modern dinocyst database Xiner Wu https://doi.org/10.1594/PANGAEA.982265

Simulation of the Transient Climate of the Last 21,000 Years (TraCE-21ka) B. L. Otto-Bliesner and N. A. Rosenbloom https://doi.org/10.5065/CXB5-TV56

Mixed layer depth climatology computed with a density threshold criterion of 0.03kg/m3 from 10 m depth value Clément de Boyer Montégut https://doi.org/10.17882/91774

Model code and software

xinerwu/MLD-Nlab: Version August 2026 (Version MLD-Nlab_v2.1) Xiner Wu https://doi.org/10.5281/zenodo.22015778

Short summary

The ocean mixed layer needs to be correctly represented in climate models to provide reliable future projections. We evaluate the mixed layer depth in 15 climate models against reconstructions for the mid-Holocene North Atlantic. The lack of meltwater input to models causes the simulated mixed layer to be deeper than reconstructed in the Labrador Sea but does not affect the Nordic Seas. Deep ocean mixing in the Labrador Sea may be particularly sensitive to ice-sheet melting under global warming.