Aragonite saturation state (Ω) from ORCA025–PISCES sensitivity experiments on Arctic terrigenous inputs (2005–2010)

This dataset provides three-dimensional fields of the aragonite saturation state (Ω), derived from global ocean biogeochemical model simulations performed with ORCA025-PISCES (0.25° horizontal resolution). The simulations include three sensitivity experiments that differ in their representation of terrigenous inputs (i.e. carbon and nutrients from rivers and coastal erosion; https://doi.org/10.17882/76983) to the ocean: ER (all terrigenous inputs), R (riverine inputs only) and NoI (no terrigenous inputs). The model, experimental design and forcing are described in detail in Terhaar et al. (2021). Although the simulations are global, the terrigenous input perturbations are confined to the Arctic Ocean. Therefore, the sensitivity experiments are not intended to quantify the influence of terrigenous inputs outside the Arctic region. Ω was computed post-simulation from simulated temperature, salinity, dissolved inorganic carbon, total alkalinity, phosphate and silicon at each time step, using the mocsy 2.0 routine (Orr et al., 2015), with equilibrium constants following best-practice recommendations (Dickson et al., 2007). The Ω data provided here represent mean conditions averaged over 2005–2010. The dataset is provided on the native curvilinear ORCA025 grid with 46 vertical levels. References: - Dickson, A. G., Sabine, C. L. and Christian, J. R. (ed.) (2007): Guide to best practices for ocean CO2 measurement. Sidney, British Columbia, North Pacific Marine Science Organization, 191pp. (PICES Special Publication 3; IOCCP Report 8). https://doi.org/10.25607/OBP-1342. - Irrgang, A. M., Tanguy, R., Petzold, P., Nitze, I., Efimova, A., Widhalm, B., Laboor, S., Jones, B., Lantuit, H., Grosse, G., and Bartsch, A. (2025): The Earth Observation for Permafrost dominated Arctic Coasts (EO4PAC) Dataset, v1, https://doi.org/10.1594/PANGAEA.974139, [dataset]. - Orr, J. C. and Epitalon, J.-M. (2015): Improved routines to model the ocean carbonate system: mocsy 2.0, Geoscientific Model Development, 8, 485–499, https://doi.org/10.5194/gmd-8-485-2015. - Terhaar, J., Lauerwald, R., Regnier, P., Gruber, N., and Bopp, L. (2021): Around one third of current Arctic Ocean primary production sustained by rivers and coastal erosion, Nature Communications, 12, 169, https://doi.org/10.1038/s41467-020-20470-z. - Vonk, J. E., Fritz, M., Speetjens, N. J., Babin, M., Bartsch, A., Basso, L. S., Bröder, L., Göckede, M., Gustafsson, O., Hugelius, G., Irrgang, A. M., Juhls, B., Kuhn, M. A., Lantuit, H., Manizza, M., Martens, J., O’Regan, M., Suslova, A., Tank, S. E., Terhaar, J., and Zolkos, S. (2025): The land–ocean Arctic carbon cycle, Nature Reviews Earth & Environment, 6, 86–105, https://doi.org/10.1038/s43017-024-00627-w.