Articles | Volume 14, issue 12
11 Dec 2018
Research article | 11 Dec 2018
Ocean carbon inventory under warmer climate conditions – the case of the Last Interglacial
Augustin Kessler et al.
No articles found.
Shuang Gao, Jörg Schwinger, Jerry Tjiputra, Ingo Bethke, Jens Hartmann, Emilio Mayorga, and Christoph Heinze
Biogeosciences, 20, 93–119,Short summary
We assess the impact of riverine nutrients and carbon (C) on projected marine primary production (PP) and C uptake using a fully coupled Earth system model. Riverine inputs alleviate nutrient limitation and thus lessen the projected PP decline by up to 0.7 Pg C yr−1 globally. The effect of increased riverine C may be larger than the effect of nutrient inputs in the future on the projected ocean C uptake, while in the historical period increased nutrient inputs are considered the largest driver.
Claire Waelbroeck, Jerry Tjiputra, Chuncheng Guo, Kerim H. Nisancioglu, Eystein Jansen, Natalia Vazquez Riveiros, Samuel Toucanne, Frédérique Eynaud, Linda Rossignol, Fabien Dewilde, Elodie Marchès, Susana Lebreiro, and Silvia Nave
Clim. Past Discuss.,
Preprint under review for CPShort summary
The precise geometry of Atlantic circulation changes that accompanied rapid climate changes of the last glacial period is still unknown. Here we combine carbon isotopic records from 18 Atlantic sediment cores with numerical simulations performed by the Norwegian Earth System Model, in order to interpret the observed isotopic changes across a cold to warm transition. Our results show that the replacement of southern-sourced by northern-sourced water plays a dominant role below ~3000 m depth.
Alban Planchat, Lester Kwiatkwoski, Laurent Bopp, Olivier Torres, James R. Christian, Momme Butenschön, Tomas Lovato, Roland Séférian, Matthew A. Chamberlain, Olivier Aumont, Michio Watanabe, Akitomo Yamamoto, Andrew Yool, Tatiana Ilyina, Hiroyuki Tsujino, Kristen M. Krumhardt, Jörg Schwinger, Jerry Tjiputra, John P. Dunne, and Charles Stock
Ocean alkalinity is critical to the uptake of atmospheric carbon and acidification in surface waters. We review the representation of alkalinity and the associated calcium carbonate cycle in Earth system models. While many parameterizations remain present in the latest generation of models, there is a general improvement in the simulated alkalinity distribution. This improvement is related to an increase in the export of biotic calcium carbonate, which closer resembles observations.
Pradeebane Vaittinada Ayar, Laurent Bopp, Jim R. Christian, Tatiana Ilyina, John P. Krasting, Roland Séférian, Hiroyuki Tsujino, Michio Watanabe, Andrew Yool, and Jerry Tjiputra
Earth Syst. Dynam., 13, 1097–1118,Short summary
The El Niño–Southern Oscillation is the main driver for the natural variability of global atmospheric CO2. It modulates the CO2 fluxes in the tropical Pacific with anomalous CO2 influx during El Niño and outflux during La Niña. This relationship is projected to reverse by half of Earth system models studied here under the business-as-usual scenario. This study shows models that simulate a positive bias in surface carbonate concentrations simulate a shift in the ENSO–CO2 flux relationship.
Nadine Goris, Klaus Johannsen, and Jerry Tjiputra
Geosci. Model Dev. Discuss.,
Revised manuscript under review for GMDShort summary
Projections of the North Atlantic carbon sink in a high-CO2 future are highly uncertain. A new study identifies key regions that dynamically explain the model spread of the future North Atlantic carbon uptake. The authors find that the upper and interior ocean volume transport at 26 N are key for a correct estimate of the North Atlantic carbon uptake. However, results indicate that models rarely perform well for both indicators, making it difficult to constrain the model uncertainty.
Filippa Fransner, Friederike Fröb, Jerry Tjiputra, Nadine Goris, Siv K. Lauvset, Ingunn Skjelvan, Emil Jeansson, Abdirahman Omar, Melissa Chierici, Elizabeth Jones, Agneta Fransson, Sólveig R. Ólafsdóttir, Truls Johannessen, and Are Olsen
Biogeosciences, 19, 979–1012,Short summary
Ocean acidification, a direct consequence of the CO2 release by human activities, is a serious threat to marine ecosystems. In this study, we conduct a detailed investigation of the acidification of the Nordic Seas, from 1850 to 2100, by using a large set of samples taken during research cruises together with numerical model simulations. We estimate the effects of changes in different environmental factors on the rate of acidification and its potential effects on cold-water corals.
Ingo Bethke, Yiguo Wang, François Counillon, Noel Keenlyside, Madlen Kimmritz, Filippa Fransner, Annette Samuelsen, Helene Langehaug, Lea Svendsen, Ping-Gin Chiu, Leilane Passos, Mats Bentsen, Chuncheng Guo, Alok Gupta, Jerry Tjiputra, Alf Kirkevåg, Dirk Olivié, Øyvind Seland, Julie Solsvik Vågane, Yuanchao Fan, and Tor Eldevik
Geosci. Model Dev., 14, 7073–7116,Short summary
The Norwegian Climate Prediction Model version 1 (NorCPM1) is a new research tool for performing climate reanalyses and seasonal-to-decadal climate predictions. It adds data assimilation capability to the Norwegian Earth System Model version 1 (NorESM1) and has contributed output to the Decadal Climate Prediction Project (DCPP) as part of the sixth Coupled Model Intercomparison Project (CMIP6). We describe the system and evaluate its baseline, reanalysis and prediction performance.
Josué Bock, Martine Michou, Pierre Nabat, Manabu Abe, Jane P. Mulcahy, Dirk J. L. Olivié, Jörg Schwinger, Parvadha Suntharalingam, Jerry Tjiputra, Marco van Hulten, Michio Watanabe, Andrew Yool, and Roland Séférian
Biogeosciences, 18, 3823–3860,Short summary
In this study we analyse surface ocean dimethylsulfide (DMS) concentration and flux to the atmosphere from four CMIP6 Earth system models over the historical and ssp585 simulations. Our analysis of contemporary (1980–2009) climatologies shows that models better reproduce observations in mid to high latitudes. The models disagree on the sign of the trend of the global DMS flux from 1980 onwards. The models agree on a positive trend of DMS over polar latitudes following sea-ice retreat dynamics.
Anne L. Morée, Jörg Schwinger, Ulysses S. Ninnemann, Aurich Jeltsch-Thömmes, Ingo Bethke, and Christoph Heinze
Clim. Past, 17, 753–774,Short summary
This modeling study of the Last Glacial Maximum (LGM, ~ 21 000 years ago) ocean explores the biological and physical changes in the ocean needed to satisfy marine proxy records, with a focus on the carbon isotope 13C. We estimate that the LGM ocean may have been up to twice as efficient at sequestering carbon and nutrients at depth as compared to preindustrial times. Our work shows that both circulation and biogeochemical changes must have occurred between the LGM and preindustrial times.
Hanna Lee, Helene Muri, Altug Ekici, Jerry Tjiputra, and Jörg Schwinger
Earth Syst. Dynam., 12, 313–326,Short summary
We assess how three different geoengineering methods using aerosol affect land ecosystem carbon storage. Changes in temperature and precipitation play a large role in vegetation carbon uptake and storage, but our results show that increased levels of CO2 also play a considerable role. We show that there are unforeseen regional consequences under geoengineering applications, and these consequences should be taken into account in future climate policies before implementing them.
Øyvind Seland, Mats Bentsen, Dirk Olivié, Thomas Toniazzo, Ada Gjermundsen, Lise Seland Graff, Jens Boldingh Debernard, Alok Kumar Gupta, Yan-Chun He, Alf Kirkevåg, Jörg Schwinger, Jerry Tjiputra, Kjetil Schanke Aas, Ingo Bethke, Yuanchao Fan, Jan Griesfeller, Alf Grini, Chuncheng Guo, Mehmet Ilicak, Inger Helene Hafsahl Karset, Oskar Landgren, Johan Liakka, Kine Onsum Moseid, Aleksi Nummelin, Clemens Spensberger, Hui Tang, Zhongshi Zhang, Christoph Heinze, Trond Iversen, and Michael Schulz
Geosci. Model Dev., 13, 6165–6200,Short summary
The second version of the coupled Norwegian Earth System Model (NorESM2) is presented and evaluated. The temperature and precipitation patterns has improved compared to NorESM1. The model reaches present-day warming levels to within 0.2 °C of observed temperature but with a delayed warming during the late 20th century. Under the four scenarios (SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5), the warming in the period of 2090–2099 compared to 1850–1879 reaches 1.3, 2.2, 3.1, and 3.9 K.
Vivek K. Arora, Anna Katavouta, Richard G. Williams, Chris D. Jones, Victor Brovkin, Pierre Friedlingstein, Jörg Schwinger, Laurent Bopp, Olivier Boucher, Patricia Cadule, Matthew A. Chamberlain, James R. Christian, Christine Delire, Rosie A. Fisher, Tomohiro Hajima, Tatiana Ilyina, Emilie Joetzjer, Michio Kawamiya, Charles D. Koven, John P. Krasting, Rachel M. Law, David M. Lawrence, Andrew Lenton, Keith Lindsay, Julia Pongratz, Thomas Raddatz, Roland Séférian, Kaoru Tachiiri, Jerry F. Tjiputra, Andy Wiltshire, Tongwen Wu, and Tilo Ziehn
Biogeosciences, 17, 4173–4222,Short summary
Since the preindustrial period, land and ocean have taken up about half of the carbon emitted into the atmosphere by humans. Comparison of different earth system models with the carbon cycle allows us to assess how carbon uptake by land and ocean differs among models. This yields an estimate of uncertainty in our understanding of how land and ocean respond to increasing atmospheric CO2. This paper summarizes results from two such model intercomparison projects that use an idealized scenario.
Lester Kwiatkowski, Olivier Torres, Laurent Bopp, Olivier Aumont, Matthew Chamberlain, James R. Christian, John P. Dunne, Marion Gehlen, Tatiana Ilyina, Jasmin G. John, Andrew Lenton, Hongmei Li, Nicole S. Lovenduski, James C. Orr, Julien Palmieri, Yeray Santana-Falcón, Jörg Schwinger, Roland Séférian, Charles A. Stock, Alessandro Tagliabue, Yohei Takano, Jerry Tjiputra, Katsuya Toyama, Hiroyuki Tsujino, Michio Watanabe, Akitomo Yamamoto, Andrew Yool, and Tilo Ziehn
Biogeosciences, 17, 3439–3470,Short summary
We assess 21st century projections of marine biogeochemistry in the CMIP6 Earth system models. These models represent the most up-to-date understanding of climate change. The models generally project greater surface ocean warming, acidification, subsurface deoxygenation, and euphotic nitrate reductions but lesser primary production declines than the previous generation of models. This has major implications for the impact of anthropogenic climate change on marine ecosystems.
Andrew H. MacDougall, Thomas L. Frölicher, Chris D. Jones, Joeri Rogelj, H. Damon Matthews, Kirsten Zickfeld, Vivek K. Arora, Noah J. Barrett, Victor Brovkin, Friedrich A. Burger, Micheal Eby, Alexey V. Eliseev, Tomohiro Hajima, Philip B. Holden, Aurich Jeltsch-Thömmes, Charles Koven, Nadine Mengis, Laurie Menviel, Martine Michou, Igor I. Mokhov, Akira Oka, Jörg Schwinger, Roland Séférian, Gary Shaffer, Andrei Sokolov, Kaoru Tachiiri, Jerry Tjiputra, Andrew Wiltshire, and Tilo Ziehn
Biogeosciences, 17, 2987–3016,Short summary
The Zero Emissions Commitment (ZEC) is the change in global temperature expected to occur following the complete cessation of CO2 emissions. Here we use 18 climate models to assess the value of ZEC. For our experiment we find that ZEC 50 years after emissions cease is between −0.36 to +0.29 °C. The most likely value of ZEC is assessed to be close to zero. However, substantial continued warming for decades or centuries following cessation of CO2 emission cannot be ruled out.
Jerry F. Tjiputra, Jörg Schwinger, Mats Bentsen, Anne L. Morée, Shuang Gao, Ingo Bethke, Christoph Heinze, Nadine Goris, Alok Gupta, Yan-Chun He, Dirk Olivié, Øyvind Seland, and Michael Schulz
Geosci. Model Dev., 13, 2393–2431,Short summary
Ocean biogeochemistry plays an important role in determining the atmospheric carbon dioxide concentration. Earth system models, which are regularly used to study and project future climate change, generally include an ocean biogeochemistry component. Prior to their application, such models are rigorously validated against real-world observations. In this study, we evaluate the ability of the ocean biogeochemistry in the Norwegian Earth System Model version 2 to simulate various datasets.
Chuncheng Guo, Mats Bentsen, Ingo Bethke, Mehmet Ilicak, Jerry Tjiputra, Thomas Toniazzo, Jörg Schwinger, and Odd Helge Otterå
Geosci. Model Dev., 12, 343–362,Short summary
In this paper, we describe and evaluate a new variant of the Norwegian Earth System Model (NorESM). It is a computationally efficient model that is designed for experiments such as paleoclimate, carbon cycle, and large ensemble simulations. The model, with various recent code updates, shows improved climate performance compared to the CMIP5 version of NorESM, while the model resolution remains similar.
Bryan C. Lougheed, Brett Metcalfe, Ulysses S. Ninnemann, and Lukas Wacker
Clim. Past, 14, 515–526,Short summary
Palaeoclimate reconstructions from deep-sea sediment archives provide valuable insight into past rapid climate change, but only a small proportion of the ocean is suitable for such reconstructions using the existing state of the art, i.e. the age–depth approach. We use dual radiocarbon (14C) and stable isotope analysis on single foraminifera to bypass the long-standing age–depth approach, thus facilitating past ocean chemistry reconstructions from vast, previously untapped ocean areas.
Siv K. Lauvset, Jerry Tjiputra, and Helene Muri
Biogeosciences, 14, 5675–5691,Short summary
Solar radiation management (SRM) is suggested as a method to offset global warming and to buy time to reduce emissions. Here we use an Earth system model to project the impact of SRM on future ocean biogeochemistry. This work underscores the complexity of climate impacts on ocean primary production and highlights the fact that changes are driven by an integrated effect of many environmental drivers, which all change in different ways.
Jörg Schwinger, Jerry Tjiputra, Nadine Goris, Katharina D. Six, Alf Kirkevåg, Øyvind Seland, Christoph Heinze, and Tatiana Ilyina
Biogeosciences, 14, 3633–3648,Short summary
Transient global warming under the high emission scenario RCP8.5 is amplified by up to 6 % if a pH dependency of marine DMS production is assumed. Importantly, this additional warming is not spatially homogeneous but shows a pronounced north–south gradient. Over the Antarctic continent, the additional warming is almost twice the global average. In the Southern Ocean we find a small DMS–climate feedback that counteracts the original reduction of DMS production due to ocean acidification.
Jörg Schwinger, Nadine Goris, Jerry F. Tjiputra, Iris Kriest, Mats Bentsen, Ingo Bethke, Mehmet Ilicak, Karen M. Assmann, and Christoph Heinze
Geosci. Model Dev., 9, 2589–2622,Short summary
We present an evaluation of the ocean carbon cycle stand-alone configuration of the Norwegian Earth System Model. A re-tuning of the ecosystem parameterisation improves surface tracer fields between versions 1 and 1.2 of the model. Focus is placed on the evaluation of newly implemented parameterisations of the biological carbon pump (i.e. the sinking of particular organic carbon). We find that the model previously underestimated the carbon transport into the deep ocean below 2000 m depth.
Roland Séférian, Marion Gehlen, Laurent Bopp, Laure Resplandy, James C. Orr, Olivier Marti, John P. Dunne, James R. Christian, Scott C. Doney, Tatiana Ilyina, Keith Lindsay, Paul R. Halloran, Christoph Heinze, Joachim Segschneider, Jerry Tjiputra, Olivier Aumont, and Anastasia Romanou
Geosci. Model Dev., 9, 1827–1851,Short summary
This paper explores how the large diversity in spin-up protocols used for ocean biogeochemistry in CMIP5 models contributed to inter-model differences in modeled fields. We show that a link between spin-up duration and skill-score metrics emerges from both individual IPSL-CM5A-LR's results and an ensemble of CMIP5 models. Our study suggests that differences in spin-up protocols constitute a source of inter-model uncertainty which would require more attention in future intercomparison exercises.
A. Kessler and J. Tjiputra
Earth Syst. Dynam., 7, 295–312,Short summary
The uncertainty of ocean carbon uptake in ESMs is projected to grow 2-fold by the end of the 21st century. We found that models that take up anomalously low (high) CO2 in the Southern Ocean (SO) today project low (high) cumulative CO2 uptake in the 21st century; thus the SO can be used to constrain future global uptake uncertainty. Inter-model spread in the SO carbon sink arises from variations in the pCO2 seasonality, specifically bias in the simulated timing and amplitude of NPP and SST.
S. K. Lauvset, N. Gruber, P. Landschützer, A. Olsen, and J. Tjiputra
Biogeosciences, 12, 1285–1298,Short summary
This paper utilizes the SOCATv2 data product to calculate surface ocean pH. The pH data are divided into 17 biomes, and a linear regression is used to derive the long-term trend of pH in each biome. The results are consistent with the trends observed at time series stations. The uncertainties are too large for a mechanistic understanding of the driving forces behind the trend, but there are indications that concurrent changes in chemistry create spatial variability.
L. Bopp, L. Resplandy, J. C. Orr, S. C. Doney, J. P. Dunne, M. Gehlen, P. Halloran, C. Heinze, T. Ilyina, R. Séférian, J. Tjiputra, and M. Vichi
Biogeosciences, 10, 6225–6245,
V. Cocco, F. Joos, M. Steinacher, T. L. Frölicher, L. Bopp, J. Dunne, M. Gehlen, C. Heinze, J. Orr, A. Oschlies, B. Schneider, J. Segschneider, and J. Tjiputra
Biogeosciences, 10, 1849–1868,
Related subject area
Subject: Carbon Cycle | Archive: Modelling only | Timescale: Millenial/D-OThe atmospheric bridge communicated the δ13C decline during the last deglaciation to the global upper oceanMysteriously high Δ14C of the glacial atmosphere: influence of 14C production and carbon cycle changesThe influence of carbonate platform interactions with subduction zone volcanism on palaeo-atmospheric CO2 since the DevonianScaling laws for perturbations in the ocean–atmosphere system following large CO2 emissionsSystematic study of the impact of fresh water fluxes on the glacial carbon cycleFingerprints of changes in the terrestrial carbon cycle in response to large reorganizations in ocean circulation
Jun Shao, Lowell D. Stott, Laurie Menviel, Andy Ridgwell, Malin Ödalen, and Mayhar Mohtadi
Clim. Past, 17, 1507–1521,Short summary
Planktic and shallow benthic foraminiferal stable carbon isotope (δ13C) data show a rapid decline during the last deglaciation. This widespread signal was linked to respired carbon released from the deep ocean and its transport through the upper-ocean circulation. Using numerical simulations in which a stronger flux of respired carbon upwells and outcrops in the Southern Ocean, we find that the depleted δ13C signal is transmitted to the rest of the upper ocean through air–sea gas exchange.
Ashley Dinauer, Florian Adolphi, and Fortunat Joos
Clim. Past, 16, 1159–1185,Short summary
Despite intense focus on the ~ 190 ‰ drop in Δ14C across the deglacial
mystery interval, the specific mechanisms responsible for the apparent Δ14C excess in the glacial atmosphere have received considerably less attention. Sensitivity experiments with the computationally efficient Bern3D Earth system model suggest that our inability to reproduce the elevated Δ14C levels during the last glacial may reflect an underestimation of 14C production and/or a biased-high reconstruction of Δ14C.
Jodie Pall, Sabin Zahirovic, Sebastiano Doss, Rakib Hassan, Kara J. Matthews, John Cannon, Michael Gurnis, Louis Moresi, Adrian Lenardic, and R. Dietmar Müller
Clim. Past, 14, 857–870,Short summary
Subduction zones intersecting buried carbonate platforms liberate significant atmospheric CO2 and have the potential to influence global climate. We model the spatio-temporal distribution of carbonate platform accumulation within a plate tectonic framework and use wavelet analysis to analyse linked behaviour between atmospheric CO2 and carbonate-intersecting subduction zone (CISZ) lengths since the Devonian. We find that increasing CISZ lengths likely contributed to a warmer Palaeogene climate.
N. Towles, P. Olson, and A. Gnanadesikan
Clim. Past, 11, 991–1007,Short summary
In this paper we find scaling relationships for perturbations to atmosphere and ocean variables from large transient CO2 emissions. We use a carbon cycle box model to calculate peak perturbations to a variety of ocean and atmosphere variables resulting from idealized emission events. As these scaling relationships depend on the physical setup, they represent a compact way of characterizing how different climates respond to large transient perturbations.
N. Bouttes, D. M. Roche, and D. Paillard
Clim. Past, 8, 589–607,
A. Bozbiyik, M. Steinacher, F. Joos, T. F. Stocker, and L. Menviel
Clim. Past, 7, 319–338,
Bentsen, M., Bethke, I., Debernard, J. B., Iversen, T., Kirkevåg, A., Seland, Ø., Drange, H., Roelandt, C., Seierstad, I. A., Hoose, C., and Kristjánsson, J. E.: The Norwegian Earth System Model, NorESM1-M – Part 1: Description and basic evaluation of the physical climate, Geosci. Model Dev., 6, 687–720, https://doi.org/10.5194/gmd-6-687-2013, 2013. a
Bleck, R., Rooth, C., Hu, D., and Smith, L. T.: Salinity-driven thermocline transients in a wind– and thermohaline–forced isopycnic coordinate model of the north Atlantic, J. Pys. Oceanogr., 22, 1486–1505, https://doi.org/10.1175/1520-0485(1992)022<1486:SDTTIA>2.0.CO;2, 1992. a, b
Brovkin, V., Brücher, T., Kleinen, T., Zaehle, S., Joos, F., Roth, R., Spahni, R., Schmitt, J., Fischer, H., Leuenberger, M., Stone, E. J., Ridgwell, A., Chapellaz, J., Kehrwald, N., Barbante, C., Blunier, T., and Jensen, D. D.: Comparative carbon cycle dynamics of the present and last interglacial, Quaternary Sci. Rev., 137, 15–32, https://doi.org/10.1016/j.quascirev.2016.01.028, 2016. a, b
Capron, E., Govin, A., Stone, E. J., Masson-Delmotte, V., Mulitza, S., Otto-Bliesner, B., Rasmussen, T. L., Sime, L. C., Waelbroeck, C., and Wolff, E. W.: Temporal and spatial structure of multi-millennial temperature changes at high latitudes during the Last Interglacial, J. Quaternary Sci., 103, 116–133, https://doi.org/10.1016/j.quascirev.2014.08.018, 2014. a
Dorthe Dahl-Jensen, Gogineni, P., and White, J. W. C.: Reconstruction of the last interglacial period from the NEEM ice core, Nature, 493, 489–489, 2013. a
Duteil, O., Koeve, W., Oschlies, A., Aumont, O., Bianchi, D., Bopp, L., Galbraith, E., Matear, R., Moore, J. K., Sarmiento, J. L., and Segschneider, J.: Preformed and regenerated phosphate in ocean general circulation models: can right total concentrations be wrong?, Biogeosciences, 9, 1797–1807, https://doi.org/10.5194/bg-9-1797-2012, 2012. a
Eppley, R. W.: Temperature and phytoplankton growth in the sea, Fish. B.-NOAA, 70, 1063–1085, 1972. a
Masson-Delmotte, V., Stenni, B., Pol, K., Braconnot, P., Cattani, O., Falourd, S., Kageyama, M., Jouzel, J., Landais, A., Minster, B., Barnola, J. M., Chappellaz, J., Krinner, G., Johnsen, S., Röthlisberger, R., Hansen, J., Mikolajewicz, U., and Otto-Bliesner, B.: EPICA Dome C record of glacial and interglacial intensities, Quaternary Sci. Rev., 29, 113–128, https://doi.org/10.1016/j.quascirev.2009.09.030, 2010. a
Menviel, L., Joos, F., and Ritz, S. P.: Simulating atmospheric CO2, δ13C and the marine carbon cycle during the Last Glaciale/Interglacial cycle: possible role for a deepening of the mean remineralization depth and an increase in the oceanic nutrient inventory, Quaternary Sci. Rev., 56, 46–68, https://doi.org/10.1016/j.quascirev.2012.09.012, 2012. a
Ninnemann, U. S., Charles, C. D., and Hodell, D. A.: Origin of global millennial scale climate events: constraints from the Southern Ocean deep sea sedimentary record, Geophysical Monograph-American Geophysical Union, 112, 99–112, 1999. a
Ridgwell, A.: Glaciale/Interglacial Perturbations in the Global Carbon Cycle, PhD thesis, University of East Anglia, Norwich, UK, 2001. a
Röthlisberger, R., Mudelsee, M., Bigler, M., de Angelis, M., Fischer, H., Hansson, M., Lambert, F., Masson-Delmotte, V., Sime, L., Udisti, R., and Wolff, E. W.: The Southern Hemisphere at glacial terminations: insights from the Dome C ice core, Clim. Past, 4, 345–356, https://doi.org/10.5194/cp-4-345-2008, 2008. a
Sarmiento, J. L., Slater, R., Barber, R., Bopp, L., Doney, S. C., Hirst, A. C., Kleypas, J., Matear, R., Mikolajewicz, U., Monfray, P., Soldatov, V., Spall, S. A., and Stouffer, R.: Response of ocean ecosystems to climate warming, Global Biogeochem. Cy., 18, GB3003, https://doi.org/10.1029/2003GB002134, 2004a. a
Schurgers, G., Mikolajewicz, U., Gröger, M., Maier-Reimer, E., Vizcaíno, M., and Winguth, A.: Dynamics of the terrestrial biosphere, climate and atmospheric CO2 concentration during interglacials: a comparison between Eemian and Holocene, Clim. Past, 2, 205–220, https://doi.org/10.5194/cp-2-205-2006, 2006. a, b
Smith, E. L.: Photosynthesis in relation to light and carbon dioxide, P. Natl. Acad. Sci. USA, 22, 504–511, 1936. a
van Heuven, S., Pierrot, D., Rae, J. W. B., Lewis, E., and Wallace, D. W. R.: Matlab program developed for CO2 system calculations. ornl/cdiac-105b., Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, US Department of Energy, Oak Ridge, Tennessee, available at: http://cdiac.ornl.gov/ftp/co2sys/CO2SYS_calc_MATLAB_v1.1/ (last access: 5 December 2018), 2011. a
Wolff, E. W., Fischer, H., Fundel, F., Ruth, U., Twarloh, B., Littot, G. C., Mulvaney, R., Röthlisberger, R., de Angelis, M., Boutron, C. F., Hansson, M., Jonsell, U., Hutterli, M. A., Lambert, F., Kaufmann, P., Stauffer, B., Stocker, T. F., Steffensen, J. P., Bigler, M., Siggaard-Andersen, M. L., Udisti, R., Becagli, S., Castellano, E., Severi, M., Wagenbach, D., Barbante, C., Gabrielli P., and Gaspari, V.: Southern Ocean sea-ice extent, productivity and iron flux over the past eight glacial cycles, Nature, 440, 491–496, https://doi.org/10.1038/nature04614, 2006. a
We analyze the changes in oceanic carbon dynamics, using a state-of-the-art Earth system model, by comparing two quasi-equilibrium states: the early, warm Eemian (125 ka) versus the cooler, late Eemian (115 ka). Our results suggest a considerably weaker ocean dissolved inorganic carbon storage at 125 ka, an alteration of the deep-water geometry and ventilation in the South Atlantic, and heterogeneous changes in phosphate availability and carbon export between the Pacific and Atlantic basins.
We analyze the changes in oceanic carbon dynamics, using a state-of-the-art Earth system model,...