Low-latitude mesopelagic nutrient recycling controls on productivity and export

doi:10.21203/rs.3.rs-3341728/v1

Download PDF

Physical Sciences - Article

Low-latitude mesopelagic nutrient recycling controls on productivity and export

https://doi.org/10.21203/rs.3.rs-3341728/v1

This work is licensed under a CC BY 4.0 License

Journal Publication

published 21 Aug, 2024

Read the published version in Nature →

Version 1

posted

You are reading this latest preprint version

Low-latitude oceans (30°S-30°N) account for approximately half of the global net primary production and export. A long-standing paradigm holds that the Southern Ocean dominates low-latitude primary production and export, with implications for the response of global primary production and export to climate change. Here we apply observational and model analyses to argue instead that 66% of low-latitude primary production and 50% of export is controlled by local mesopelagic macronutrient recycling. An additional supply of nutrients locally upwelled from the deep ocean balances the loss of nutrients to the deep ocean via the soft tissue pump, with only a 5% supply through shallow (considered over the upper 870m) transfer from the Southern Ocean. Further analyses of a set of five CMIP6 models run to 2300 under high emissions reveal significant disparities in their projections of not only the amplitude but also the sign of low latitude primary production, with temperature-dependent remineralization promoting enhanced low-latitude mesopelagic nutrient retention and associated increases in primary production through low-latitude overturning and upwelling. This underscores the importance of mechanistic understanding of mesopelagic remineralization and its sensitivity to ocean warming for predicting future ecosystem changes.

Earth and environmental sciences/Ocean sciences/Marine chemistry

Earth and environmental sciences/Climate sciences/Biogeochemistry/Element cycles

The low-latitude ocean regions, considered as the expanse between the subtropical convergence zones (30°S-30°N), are important for both their rich biodiversity as well as for fisheries and food security^1-3. Both marine primary productivity (PP) and export over this region account for approximately half of their respective global totals⁴. Large PP and export occur in low-latitude oceans despite thermocline macronutrient concentrations being less than half of what is found in subpolar/circumpolar regions, indicating vigorous decadal renewal timescales for thermocline waters through the shallow overturning circulation^5-7. An Earth system model has previously been considered under strong anthropogenic forcing (historical/RCP85) to argue that low-latitude (30°S-30°N) export and PP could decrease by 41% and 24% respectively by 2300 relative to the present climate state⁸. This collapse was attributed to a cascade of processes, initially triggered by sea ice retreat over the Southern Ocean, which in turn induced Southern Ocean subsurface nutrient trapping. Reduced surface nutrient concentrations in the Southern Ocean in turn lead to reduced nutrients exported northward to the low-latitude thermocline in mode and intermediate waters. This work is important in emphasizing a first-order role for a low-latitude response in PP and export under multi-century climate perturbations. The interpretation, however, invoked the mechanisms presented in an earlier analysis⁹, which found that 75% of low-latitude new production is contingent on a sustained supply of nutrients from the Southern Ocean using an ocean biogeochemistry model. A subsequent study with an inverse ocean biogeochemical model identified a contribution of 44% to PP to the north of 40°S as being due to Southern Ocean nutrient trapping¹⁰, thereby also arguing for a first-order role for the Southern Ocean. However, independent observational analyses indicate that at least for the case of the Pacific basin, the Subantarctic Mode Water water mass cannot readily access regions north of 20°S due to strong potential vorticity barriers¹¹.

We are thereby motivated to propose that low-latitude PP and export are sustained primarily by processes local to the tropics, and that the sensitivity to non-local perturbations over the Southern Ocean is more modest than that previously proposed ⁹. In particular, we propose that remineralization within the low-latitude mesopelagic domain (LLMD) (defined here to span 30°S-30°N and 150m-870m) and rapid subsequent re-emergence of nutrients through the shallow overturning structures within the low-latitudes are the dominant driver of low-latitude PP and export. This is investigated through the combined use of in-situ observations and a new suite of model sensitivity studies with a fully prognostic global ocean biogeochemistry model.

We examine the extent to which local nutrient recycling in the tropics contributes to sustaining low-latitude PP and export by quantifying its contribution to the total low-latitude mesopelagic nutrient inventory (here we use phosphate, or PO₄^3-) using an observational product based on hydrographic measurements, GLODAPv2^12,13. We invoke a well-known diagnostic that decomposes total PO₄^3- concentrations^14,15 into two components: a preformed component that represents the PO₄^3- concentrations at the surface when a new water mass is transferred from the surface into the interior by subduction, and a regenerated component that reflects the cumulative impact of respiration of organic matter that increases PO₄^3- concentrations as the water mass is transported in the ocean interior.

The distribution of PO₄^3- on the mid-thermocline density horizon s₀=25.5 kg m^-3 in the ocean interior (Fig. 1a) reveals concentrations that are maximum in the equatorial band. Over the same density horizon the regenerated fraction of PO₄³ (Fig. 1b) is larger than 50 percent over much of the region between 20°S and 20°N, with exceptions (minimum values) neighboring subduction regions. On the density layer associated with the upper boundary of Subantarctic Mode Water (SAMW) formed in the Southern Ocean and entering the Pacific Ocean just below the thermocline (s₀=26.8 kg m^-3)¹⁶, the PO₄^3- concentrations are higher than in the thermocline (Fig. 1c). Additionally, the regenerated fraction of PO₄^3- is modestly higher than 50% throughout most of the tropics (Fig. 1d). Viewed north-south along 150°W in the Pacific, despite the large vertical gradients in PO₄^3- concentrations across the equatorial thermocline (Fig. 1e), the regenerated fraction exhibits remarkable homogeneity with values just above 50% over the region 10°S-10°N and 150m-700m. Further sensitivity analysis with varying stochiometric ratios of O₂: PO₄^3- indicates that the substantial regenerated pool of PO₄^3- identified here is relatively insensitive to our choice of a ratio (Extended Data Fig. 1),

Here we hypothesize that the large regenerated nutrient pool in the low-latitudes provides a dominant control on the elevated low-latitude PP and export through local processes. To test this hypothesis, we apply a set of perturbation simulations with the PISCES-v2 biogeochemistry model¹⁷ (see methods) that all use identical circulation fields but that vary by perturbing nutrient remineralization in distinct latitude bands. In PISCES-v2, the export of organic material from the euphotic zone to the interior of the ocean is represented by the gravitational sedimentation of two particulate pools that differ by their mean size, and thus by their sinking speed. These particulate pools are continuously solubilized to dissolved organic matter according to a temperature-dependent rate. This dissolved pool is then ultimately remineralized to inorganic nutrients. In addition to a standard experiment (STD)¹⁷, we performed a series of perturbation experiments in which remineralization of nutrients and solubilization of organic carbon is disallowed within specific latitude-bounded regions (see Methods for model perturbation details). For PERT_TROP, solubilization was disallowed within the tropics over the depths comprising mode and intermediate waters (30°S-30°N, 150m-1500m). For PERT_SOUTH and PERT_NORTH, solubilization was disallowed between 150m and the next-to-bottom grid-box of the model domain, over 90°S-30°S and 30°N-90°N, respectively.

A comparison of the STD and TROP_PERT experiments reveals a large reduction in PP and export over the low-latitude domain when local mesopelagic remineralization is disallowed (Fig. 2). For STD, PP and export are 21.5 PgC yr^-1 and 2.73 PgC yr^-1, respectively, when integrated over 30°S-30°N. For PERT_TROP, PP and export are 7.3 and 1.37 PgC yr^-1, respectively, over the same domain. Thus PERT_TROP represents a 66% drop in PP and a 50% drop in export relative to STD over 30°S-30°N. These changes are larger than the 17% reduction in PP and 38% decrease in export found for the PERT_SOUTH case (maps showing perturbation patterns for PERT_SOUTH and PERT_NORTH are shown in Extended Data Figs. 2 and 3, respectively). Proper attribution of the strong sensitivities under PERT_TROP relative to STD is facilitated by a coarse-graining of the modeled PO₄^3- budget in the LLMD spanning 30°S-30°N and 150m-870m (Fig. 3; the full budgets for all four simulations are shown in Extended Data Fig. 4). For STD (budgets in black) PP is 21.5 PgC yr^-1, the vertical flux of soft tissue and dissolved organic phosphorous (DOP) into the LLMD is 2.73 PgC yr^-1, while the soft tissue flux out of the LLMD at 870m is 0.88 PgC yr^-1 (DOP fluxes are negligible), with a net solubilization source within the LLMD (largest in the shallower thermocline layers) of 1.72 PgC yr^-1. As such, the regenerated PO₄ represents 63% of the net upward flux of PO₄^3- across the 150m horizon within the tropics. The net meridional fluxes (the sum of both northward and southward fluxes) of PO₄^3- across 30°S and 30°N, on the other hand, present a net divergence that depletes PO₄^3- over the LLMD. For the PERT_TROP case (red numbers) low-latitude remineralization was disallowed between 150m-1500m, and the -0.1 PgC yr^-1 of interior production corresponds to a degree of PP occurring just below 150m depth. The increase in the upward flux of PO₄^3- across 870m by 0.12 PgC yr^-1 and the net reduction of meridional divergence across 30°S and 30°N by 0.2 PgC yr^-1 indicate that there are feedbacks that reduce the loss of PO₄^3- and thereby dampen the drop in export for PERT_TROP.

The PERT_TROP perturbation relative to STD (Fig. 3) underscores that the dominant process sustaining elevated low-latitude PP and export is local resolubilization (mainly through remineralization) of PO₄^3- locally within the local LLMD, in conjunction with the subsequent local re-emergence into the low-latitude euphotic zone. The upward net flux of PO₄^3- across 870m into the LLMD plays a critical supporting role in balancing not only the downward particle flux across 870m, but also in compensating for the net meridional divergence of PO₄^3- out of the LLMD across 30°S and 30°N. A previous study¹⁸ considered a role for remineralization in sustaining low latitude new production, but under the assumption that regenerated nutrients are a downstream legacy of new/preformed nutrients supplied through SAMW, thereby not accounting for a sizable low-latitude remineralized pool of PO₄^3- sustained through local low-latitude processes. The same study also ruled out a role for supply from the deep ocean.

In our interpretation, the remineralized low-latitude pool is a legacy of the deeper low-latitude upwelling of preformed PO₄^3- that is originally sourced in the deep-water formation regions of the Southern Ocean. The net upwelling flux of 8 Sv across 870m in the global tropics (Extended Data Fig. 5) in the model circulation state is consistent with a deep upwelling cell in the low-latitudes that has been identified with observational constraints¹⁹ and is also characteristic of a broad range of climate models^20,21. In fact the main impact of our PERT_SOUTH experiment is to enhance the net divergence (0.4 PgC yr^-1 relative to STD) of the regenerated PO₄^3- pool from the low-latitudes (Extended Data Fig. 4).

Our results also motivate us to reconsider previous modeling work showing substantial low-latitude PP and export decreases under sustained warming to the year 2300 ⁸. Here we consider five CMIP6 models: IPSL-CM6A²², CESM2-WACCM²³, UKESM1²⁴, ACCESS-ESM1.5²⁵, and MIROC-ES2L²⁶ , run to 2300 under high emissions forcing (SSP5-8.5)²⁷. Anomalies of primary production for each model relative to the period 1850-1900 are shown in Fig. 4a (corresponding thermal fields are shown in Extended Data Fig. 6), revealing a pronounced divergence in not only the amplitude of PP but also the sign of the response. This divergence of the global response across CMIP6 models is best interpreted as a measure of the very large uncertainty in PP, under the assumption that each of the models presents an equally likely outcome under strong and persistent anthropogenic climate perturbations. The divergence of the globally integrated primary production (Fig. 4a) is in fact largely sustained over 30°S-30°N (Fig. 4b), with the low-latitude response reflecting an underlying diversity of low-latitude mechanisms or process-parameterizations^28,29. As the increase in PP over 30°S-30°N for two of the models (IPSL-CM6A and ACCESS-ESM1.5) is not at face value consistent with the Southern Ocean-triggered nutrient trapping mechanism emphasized previously⁸, we address whether the low latitude nutrient recycling mechanism highlighted in Figs. 2 and 3 may be contributing.

To this end, we consider the fractional changes in zonal mean ocean interior PO₄^3- concentrations for the cases of the IPSL-CM6A (Fig. 4c) (increasing low-latitude PP) and CESM2-WACCM (Fig. 4d) (decreasing low-latitude PP) models between the 1990s and 2290s. For a mean over the 1990s with both models, the transfer efficiency defined as the ratio of the soft tissue flux at 780m relative to 150m, is 27% for IPSL-CM6A and 29% for CESM2-WACCM over the tropics (Extended Data Tables 1 and 2). However, by the 2290s, transfer efficiency over the tropics has reduced to 21% for IPSL-CM6A (enhanced thermocline nutrient retention) and has increased to 34% in CESM2-WACCM (decreased thermocline nutrient retention), as is reflected in the perturbations to zonally averaged PO₄^3- between the 1990s and 2290s for both models in Fig. 4. This difference between the two models reflects the fact that remineralization in PISCES-v2 is temperature-dependent and thereby enhanced under sustained warming, whereas for the MARBL biogeochemistry component of CESM2-WACCM the temperature dependence of remineralization remains static for CMIP6 transient simulations³⁰. As such, these differences in representation of remineralization and ensuing thermocline nutrient retention contribute to a modest increase in export for IPSL-CM6A of 0.3% by the year 2300, and a reduction by 38% for CESM2-WACCM. This underscores the importance of improved process-understanding and model representation of remineralization for projecting future changes in marine biological production and export³¹, and as a consequence the ability of marine ecosystems to sustain food provision and other services³².

Observation-derived products

For the analysis of the resolubilized fractions of nutrients, we use GLODAPv2^12,13 data product. The repeat hydrographic observational components of this global synthesis product have been consistently quality-controlled for comparisons between cruises conducted by different laboratories.

For the analysis in Fig. 1, where the large pool of regenerated PO₄^3- is identified for the low-latitude mesopelagic domain, the identification of this regenerated pool makes use of a deconvolution of preformed and regenerated fractions of PO₄^3- using a long-standing method¹⁴ for the case of NO₃^-, through the use of apparent oxygen utilization (AOU). We define the regenerated fraction of PO₄^3- to be

PO4_regen = (PO₄^3- – PO₄^3-*)/ PO₄^3-

Where PO₄^3- is the preformed PO₄^3- concentration inferred as:

PO₄* = PO₄^3- – AOU*170.

Where the 170 multiplier in the latter expression represents a widely-used stochiometric ratio³³. The uncertainty in the amplitude of PO4_regen due to uncertainty in the stochiometric ratio is described in Extended Data Fig. 1, where it is seen that the identification of the large pool of regenerated PO₄³ (PO4_regen>50%) is robust to uncertainty in the values for the stochiometric ratio, where we have used the value of 138³⁴ for comparison. When applying this framework to ocean interior fields, one usually makes two assumptions: (i) O₂ concentrations are at saturation with atmospheric O₂ in the mixed layer of the ocean at the time of subduction, and (ii) ocean interior circulation is to first order a largely adiabatic process along constant density (isopycnal) horizons, and (iii) there is a relatively constrained relationship between the rate of O₂ consumption and PO₄^3- production through respiration, such that a deconvolution of the preformed and regenerated fractions can be identified using temperature, salinity, and O₂ concentrations, along with PO₄^3- concentrations.

NEMO-PISCES model simulations

The biogeochemical model considered here is PICES-v2 (Pelagic Interactions Scheme for Carbon and Ecosystem Studies, version 2)¹⁷. The model is designed to simulate the lower trophic levels of ocean ecosystems (phytoplankton, microzooplankton, and mesozooplankton), as well as the marine biogeochemical cycling of carbon and the major nutrients (P, N, Fe, and Si). The runs considered here represent the coupling of PISCES-v2 to the ORCA2 configuration of the Nucleus for European Modelling of the Ocean (NEMO) model version 3.6. The ORCA2 configuration has nominally two-degree horizontal resolution with meridional refinement to 0.5° near the equator, with 30 vertical levels. As with the presentation study for PISCES-v2¹⁷, the PISCES-v2 simulations use identical five-day averaged climatological physical state variables to drive the biogeochemical model offline. Each of the four runs described in the main text was run for more than 5000 years.

In addition to the control (STD) simulation for which the PISCES_v2¹⁷, the three perturbation simulations were conducted by disallowing solubilization of organic carbon, PO₄^3-, and NO₃^- in the ocean interior (below 150m depth) within three specific latitude bands. The horizon of 150m was chosen to define the base of the euphotic zone. For PERT_NORTH this is applied over 30°N-90°N, for PERT_SOUTH over 90°S-30°S, and for PERT_TROP over 30°S-30°N. For PERT_NORTH and PERT_SOUTH is deactivated between 150m and the bottom model grid cell in the model. For the PERT_TROP simulation, it was decided to disallow remineralization over the depth range 150m-1500m, with this depth range including all water masses comprised by the wind-driven circulation, ranging from thermocline to subpolar mode waters to intermediate waters.

Acknowledgments:

The authors would like to thank Jorge Sarmiento for his iterative feedback and constructive comments through the development of this project. We would also like to thank Lester Kwiatkowski for his feedback and constructive comments.

Funding:

KBR was supported by the Institute for Basic Sciences (IBS), Republic of Korea, under IBS-R028-D1 (KR).

DB acknowledges support from US NSF grant OCE-1847687.

KT and MI received support from the Japan Meteorological Research Institute research fund C4 for the study of ocean biogeochemistry and acidification.

Author contributions:

Conceptualization: KBR, OA

Methodology: KBR, OA

Investigation: KBR, OA, KT, DS

Visualization: KBR, OA, KT, RY

Writing – original draft: KBR, OA

Writing – review & editing: KBR, OA, KT, LR, MI, TN, DS, RY, DB

Competing interests: Authors declare that they have no competing interests.

Data and materials availability: The data and code used in the study will be made publicly available upon publication of the article.

FAO. The state of world fisheries and aquaculture 2012. (Food and Agriculture Organization of the United Nations, Rome, 2012).
Costello, C. et al. The future of food from the sea. Nature 588, 95-100 (2020).
Blanchard, J. L. et al. Linked sustainability challenges and trade-offs among fisheries, aquaculture and agriculture. Nature ecology & evolution 1, 1240-1249 (2017).
Dunne, J. P., Sarmiento, J. L. & Gnanadesikan, A. A synthesis of global particle export from the surface ocean and cycling through the ocean interior and on the seafloor. Global Biogeochemical Cycles 21 (2007). https://doi.org:10.1029/2006gb002907
Fine, R. A., Maillet, K. A., Sullivan, K. F. & Willey, D. Circulation and ventilation flux of the Pacific Ocean. Journal of Geophysical Research-Oceans 106, 22159-22178 (2001). https://doi.org:10.1029/1999jc000184
Aumont, O., Orr, J. C., Monfray, P., Madec, G. & Maier‐Reimer, E. Nutrient trapping in the equatorial Pacific: The ocean circulation solution. Global Biogeochemical Cycles 13, 351-369 (1999).
Toyama, K. et al. Large Reemergence of Anthropogenic Carbon into the Ocean's Surface Mixed Layer Sustained by the Ocean's Overturning Circulation. Journal of Climate 30, 8615-8631 (2017). https://doi.org:10.1175/jcli-d-16-0725.1
Moore, J. K. et al. Sustained climate warming drives declining marine biological productivity. Science 359, 1139-1142 (2018). https://doi.org:10.1126/science.aao6379
Sarmiento, J. L., Gruber, N., Brzezinski, M. A. & Dunne, J. P. High-latitude controls of thermocline nutrients and low latitude biological productivity. Nature 427, 56-60 (2004).
Primeau, F. W., Holzer, M. & DeVries, T. Southern Ocean nutrient trapping and the efficiency of the biological pump. Journal of Geophysical Research: Oceans 118, 2547-2564 (2013).
Herraiz-Borreguero, L. & Rintoul, S. R. Subantarctic mode water: Distribution and circulation. Ocean Dynamics 61, 103-126 (2011).
Olsen, A. et al. The Global Ocean Data Analysis Project version 2 (GLODAPv2) - an internally consistent data product for the world ocean. Earth System Science Data 8, 297-323 (2016). https://doi.org:10.5194/essd-8-297-2016
Lauvset, S. K. et al. A new global interior ocean mapped climatology: the 1° x 1° GLODAP version 2. Earth System Science Data 8, 325-340 (2016). https://doi.org:10.5194/essd-8-325-2016
Broecker, W. S. "NO", A Conservative Water-Mass Tracer. Earth and Planetary Science Letters 23, 100-107 (1974). https://doi.org:10.1016/0012-821x(74)90036-3
Ito, T. & Follows, M. J. Preformed phosphate, soft tissue pump and atmospheric CO₂. Journal of Marine Research 63, 813-839 (2005). https://doi.org:10.1357/0022240054663231
Cerovečki, I. & Meijers, A. J. S. Strong quasi-stationary wintertime atmospheric surface pressure anomalies drive a dipole pattern in the Subantarctic Mode Water formation. Journal of Climate 34, 6989-7004 (2021).
Aumont, O., Ethe, C., Tagliabue, A., Bopp, L. & Gehlen, M. PISCES-v2: an ocean biogeochemical model for carbon and ecosystem studies. Geoscientific Model Development 8, 2465-2513 (2015). https://doi.org:10.5194/gmd-8-2465-2015
Palter, J. B., Sarmiento, J. L., Gnanadesikan, A., Simeon, J. & Slater, R. D. Fueling export production: nutrient return pathways from the deep ocean and their dependence on the Meridional Overturning Circulation. Biogeosciences 7, 3549-3568 (2010). https://doi.org:10.5194/bg-7-3549-2010
Talley, L. D., Reid, J. L. & Robbins, P. E. Data-based meridional overturning streamfunctions for the global ocean. Journal of Climate 16, 3213-3226 (2003). https://doi.org:10.1175/1520-0442(2003)016<3213:dmosft>2.0.co;2
Sen Gupta, A. et al. Future changes to the Indonesian Throughflow and Pacific circulation: The differing role of wind and deep circulation changes. Geophysical Research Letters 43, 1669-1678 (2016). https://doi.org:10.1002/2016gl067757
Feng, M., Zhang, X. B., Sloyan, B. & Chamberlain, M. Contribution of the deep ocean to the centennial changes of the Indonesian Throughflow. Geophysical Research Letters 44, 2859-2867 (2017). https://doi.org:10.1002/2017gl072577
Boucher, O. et al. Presentation and Evaluation of the IPSL-CM6A-LR Climate Model. Journal of Advances in Modeling Earth Systems 12 (2020). https://doi.org:10.1029/2019ms002010
Danabasoglu, G. et al. The Community Earth System Model Version 2 (CESM2). Journal of Advances in Modeling Earth Systems 12, 35 (2020). https://doi.org:10.1029/2019ms001916
Sellar, A. A. et al. UKESM1: Description and Evaluation of the UK Earth System Model. Journal of Advances in Modeling Earth Systems 11, 4513-4558 (2019). https://doi.org:10.1029/2019ms001739
Ziehn, T. et al. The Australian earth system model: ACCESS-ESM1. 5. Journal of Southern Hemisphere Earth Systems Science 70, 193-214 (2020).
Hajima, T. et al. Development of the MIROC-ES2L Earth system model and the evaluation of biogeochemical processes and feedbacks. Geoscientific Model Development 13, 2197-2244 (2020). https://doi.org:10.5194/gmd-13-2197-2020
Meinshausen, M. et al. The shared socio-economic pathway (SSP) greenhouse gas concentrations and their extensions to 2500. Geoscientific Model Development 13, 3571-3605 (2020).
Séférian, R. et al. Tracking Improvement in Simulated Marine Biogeochemistry Between CMIP5 and CMIP6. Current Climate Change Reports 6, 95-119 (2020). https://doi.org:10.1007/s40641-020-00160-0
Bopp, L. et al. Diazotrophy as a key driver of the response of marine net primary productivity to climate change. Biogeosciences 19, 4267-4285 (2022).
Long, M. C. et al. Simulations with the Marine Biogeochemistry Library (MARBL). (2021). https://doi.org:https://doi.org/10.1002/essoar.10507358.1
Cram, J. A. et al. The role of particle size, ballast, temperature, and oxygen in the sinking flux to the deep sea. Global Biogeochemical Cycles 32, 858-876 (2018).
Cooley, S. et al. in IPCC AR6 WGII (Cambridge University Press, 2022).
Anderson, L. A. & Sarmiento, J. L. Redfield Ratios of Remineralization Determined by Nutrient Data-Analysis. Global Biogeochemical Cycles 8, 65-80 (1994). https://doi.org:10.1029/93gb03318
Redfield, A. C. On the proportions of organic derivatives in sea water and their relation to the composition of plankton. Vol. 1 p. 177-192 (University Press of Liverpool, 1934).
Boucher, O. et al. (2018).
Ziehn, T. et al. (2019).
Hajima, T. et al. MIROC MIROC-ES2L model output prepared for CMIP6 CMIP historical. Earth System Grid Federation. Available online at https://doi. org/10.22033/ESGF/CMIP6 5602 (2019).

There is NO Competing Interest.

ExtendedData.docx

Download PDF

Journal Publication

published 21 Aug, 2024

Read the published version in Nature →

Version 1

posted

You are reading this latest preprint version

Low-latitude mesopelagic nutrient recycling controls on productivity and export

Status:

Journal Publication

Version 1

Abstract

Figures

Main text

METHODS

Declarations

References

Additional Declarations

Supplementary Files

Status:

Journal Publication

Version 1