Methods

REcoM - in its current standard set-up - carries 21 tracers, including dissolved inorganic carbon and alkalinity for the carbonate system, oxygen, the macronutrients dissolved inorganic nitrogen (DIN) and silicic acid and the trace metal iron. REcoM3 has two phytoplankton classes, small phytoplankton (with implicit representation of calcifiers) and diatoms. The intracellular stoichiometry of C:N:Si:Chl pools for diatoms and C:N:CaCO3:Chl pools for small phytoplankton is allowed to respond dynamically to environmental conditions following Geider et al., 1998. The intracellular iron pool is a function of the intracellular nitrogen concentration (fixed Fe:N) as iron is physiologically linked to enzyme formation, especially the photosynthetic electron transport chain (Raven, 1988; Behrenfeld & Milligan, 2013). Dead organic matter is transferred to detritus by aggregation and grazing by two zooplankton class and the sinking and advection of detritus is represented explicitly. Recent work has extended the description of plankton functional types to three phytoplankton groups (coccolithophores, small phytoplankton, diatoms, Seifert et al., 2022) and three zooplankton groups (micro-, meso- and macrozooplankton, Karakuş et al., 2022), and to include the sensitivity of phytoplankton growth to ocean acidification (Seifert et al., 2022).

Main REcoM references (chronological order):

•[3 phytoplankton functional groups and CO2 sensitivity] Seifert, M., Nissen, C., Rost, B., Hauck, J., 2022. Cascading effects augment the direct impact of CO2 on phytoplankton growth in a biogeochemical model. Elementa: Science of the Anthropocene 10, https://doi.org/10.1525/elementa.2021.00104

•[3 zooplankton functional groups] Karakuş, O., Völker, C., Iversen, M., Hagen, W., Hauck, J., 2022. The Role of Zooplankton Grazing and Nutrient Recycling for Global Ocean Biogeochemistry and Phytoplankton Phenology. JGR Biogeosciences 127. https://doi.org/10.1029/2022JG006798

•[Air-sea CO2 fluxes in FESOM-REcoM] Hauck, J., Zeising, M., Le Quéré, C., Gruber, N., Bakker, D.C.E., Bopp, L., Chau, T.T.T., Gürses, Ö., Ilyina, T., Landschützer, P., Lenton, A., Resplandy, L., Rödenbeck, C., Schwinger, J., Séférian, R., 2020. Consistency and Challenges in the Ocean Carbon Sink Estimate for the Global Carbon Budget. Front. Mar. Sci. 7, 571720. https://doi.org/10.3389/fmars.2020.571720

•[Arctic high-resolution] Schourup-Kristensen, V., Wekerle, C., Wolf-Gladrow, D., Völker, C. (2018): Arctic Ocean biogeochemistry in the high resolution FESOM 1.4-REcoM2 model, Progress in Oceanography, 168, 65-81, doi:10.1016/j.pocean.2018.09.006

•[First coupling to FESOM] Schourup-Kristensen, V., Sidorenko, D., Wolf-Gladrow, D. A. and Völker, C. (2014). A skill assessment of the biogeochemical model REcoM2 coupled to the Finite Element Sea Ice-Ocean Model (FESOM 1.3), Geoscientific Model Development, 7 (6), 2769-2802, doi:10.5194/gmd-7-2769-2014

•[MITgcm version] Hauck, J., Völker, C., Wang, T., Hoppema, M., Losch, M. and Wolf-Gladrow, D. A. (2013). Seasonally different carbon flux changes in the Southern Ocean in response to the southern annular mode, Global Biogeochemical Cycles, 27 (4), 1236-1245, doi:10.1002/2013GB004600

•[Initial REcoM paper] Schartau, M., A. Engel, J. Schröter, S. Thoms, C. Völker, and D. Wolf-Gladrow (2007), Modelling carbon overconsumption and the formation of extracellular particulate organic carbon, Biogeosciences, 4, 433–454, doi:10.5194/bg-4-433-2007

FESOM, AWI-ESM

FESOM (Finite-Element/volumE Sea ice-Ocean Model) is a multi-resolution sea ice-ocean model that solves the equations of motion on unstructured meshes. The model is developed and supported by researchers at the Alfred Wegener

Institute, Helmholtz Centre for Polar and Marine Research (AWI).