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| Bouttes, N.; Paillard, D.; Roche, D. M.; Waelbroeck, C.; Kageyama, M.; Lourantou, A.; Michel, E.; Bopp, L.. |
| During the last termination (from similar to 18 000 years ago to similar to 9000 years ago), the climate significantly warmed and the ice sheets melted. Simultaneously, atmospheric CO2 increased from similar to 190 ppm to similar to 260 ppm. Although this CO2 rise plays an important role in the deglacial warming, the reasons for its evolution are difficult to explain. Only box models have been used to run transient simulations of this carbon cycle transition, but by forcing the model with data constrained scenarios of the evolution of temperature, sea level, sea ice, NADW formation, Southern Ocean vertical mixing and biological carbon pump. More complex models (including GCMs) have investigated some of these mechanisms but they have only been used to try... |
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| Ano: 2012 |
URL: https://archimer.ifremer.fr/doc/00214/32514/31004.pdf |
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| Tagliabue, A.; Bopp, L.; Roche, D. M.; Bouttes, N.; Dutay, J. -c.; Alkama, R.; Kageyama, M.; Michel, E.; Paillard, D.. |
| We use a state-of-the-art ocean general circulation and biogeochemistry model to examine the impact of changes in ocean circulation and biogeochemistry in governing the change in ocean carbon-13 and atmospheric CO2 at the last glacial maximum (LGM). We examine 5 different realisations of the ocean's overturning circulation produced by a fully coupled atmosphere-ocean model under LGM forcing and suggested changes in the atmospheric deposition of iron and phytoplankton physiology at the LGM. Measured changes in carbon-13 and carbon-14, as well as a qualitative reconstruction of the change in ocean carbon export are used to evaluate the results. Overall, we find that while a reduction in ocean ventilation at the LGM is necessary to reproduce carbon-13 and... |
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| Ano: 2009 |
URL: https://archimer.ifremer.fr/doc/00218/32919/31408.pdf |
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| Husson, L.; Pastier, A. -m.; Pedoja, K.; Elliot, M.; Paillard, D.; Authemayou, C.; Sarr, A. -c.; Schmitt, A.; Cahyarini, S. Y.. |
| Global variations in reef productivity during the Quaternary depend on external parameters that may alter the global chemical balance in the oceans and atmosphere. We designed a numerical model that simulates reef growth, erosion, and sedimentation on coastlines undergoing sea level oscillations, and uplift or subsidence. We further develop a probabilistic evaluation that accounts for variable vertical ground motion, erosion, and foundation morphologies. Absolute sea level change appears primordial, as productivity must have increased by an order of magnitude since the onset of the glacial cycles, approximate to 2.6 Ma. But most important is relative sea level change, i.e., eustasy modulated by uplift or subsidence, that rejuvenates the accommodation space... |
| Tipo: Text |
Palavras-chave: Coral reefs; Sea level; Carbonate; Modeling; Paleoclimate. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00638/74993/75789.pdf |
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