This dataset contains the results (micropaleontology data and climatic simulations) of a paper published in Nature in 2021 entitled "Cyclic evolution of phytoplankton forced by changes in tropical seasonality" (https://doi.org/10.21203/rs.3.rs-100744/v1). It shows that eccentricity, in low latitudes, directly drives the changes in seasonality that influence the evolution of coccolithophores and the carbonate fluxes. 

The dataset describes the Pleistocene history of the morphology and the mass accumulation rate of Noelaerhabdaceae (Genus Emiliania, Gephyrocapsa, Reticulofenestra and Pseudoemiliania) coccoliths, measured in 9 Tropical Indo-Pacific sequences retrieved during IODP (Exp353 and Exp363) and IMAGES (expeditions 3 (MD106) and 13 (MD148)) expeditions (MD05-2920, MD05-2930, MD97-2140, U1443, U1446, U1448, U1483, U1485, and U1486).  This dataset has been established by an automated microscopy system based on Convolutional Neural Networks and morphometry.

The morphology parameters considered are the length (size in µm) and the mass (in pg) of the coccoliths. Those parameters are used to calculate a newly developed index of morphological divergence. The tables are those directly used to prepare the figures of Beaufort et al., Nature, 2021.

The climatic simulation tables present the variability of the ocean-atmosphere system in response to eccentricity and its impact on ocean biogeochemistry. This dataset contains atmosphere, ocean and ocean biogeochemistry outputs from modeling experiments with variable orbital configurations that target the effect of eccentricity on the climate system (Beaufort et al. 2021). The simulations have been run using the IPSL-CM5A2 General Circulation Model (Sepulchre et al. 2020 - GMD). It includes 7 simulations with pre-industrial boundary conditions (CO2, ice-sheet, paleogeography) and different set of realistic eccentricity/precession/obliquity configurations (at 2.222, 2.230, 2.265, 2.346, 2.369, 2.380 and 2.395  Ma).

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