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4. Modern and glacial tropical snowlines controlled by sea surface temperature and atmospheric mixing

Author

Tripati, AK, Sahany, S, Pittman, D, Eagle, RA, Neelin, JD, Mitchell, JL, and Beaufort, L

Subjects
Meteorology & Atmospheric Sciences
Abstract

During the Last Glacial Maximum, tropical sea surface temperatures were 1 to 3C cooler than present, but the altitude of the snowlines of tropical glaciers was lower than would be expected in light of these sea surface temperatures. Indeed, both glacial and twentieth-century snowlines seem to require lapse rates that are steeper than a moist adiabat. Here we use estimates of Last Glacial Maximum sea surface temperature in the Indo-Pacific warm pool based on the clumped isotope palaeotemperature proxy in planktonic foraminifera and coccoliths, along with radiative-convective calculations of vertical atmospheric thermal structure, to assess the controls on tropical glacier snowlines. Using extensive new data sets for the region, we demonstrate that mean environmental lapse rates are steeper than moist adiabatic during the recent and glacial. We reconstruct glacial sea surface temperatures 4 to 5C cooler than modern. We include modern and glacial sea surface temperatures in calculations of atmospheric convection that account for mixing between rising air and ambient air, and derive tropical glacier snowlines with altitudes consistent with twentieth-century and Last Glacial Maximum reconstructions. Sea surface temperature changes ≤3C are excluded unless glacial relative humidity values were outside the range associated with deep convection in the modern. We conclude that the entrainment of ambient air into rising air masses significantly alters the vertical temperature structure of the troposphere in modern and ancient regions of deep convection. Furthermore, if all glacial tropical temperatures were cooler than previously estimated, it would imply a higher equilibrium climate sensitivity than included in present models. © 2014 Macmillan Publishers Limited.

Published
2014

5. Rapid diversification underlying the global dominance of a cosmopolitan phytoplankton

Author

Bendif, EM, Probert, I, Archontikis, OA, Young, JR, Beaufort, L, Rickaby, RE, Filatov, D, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), and Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDE]Environmental Sciences, population genetics, microbial biooceanography, phylogenomics, [SDV.BID]Life Sciences [q-bio]/Biodiversity, Microbiology, Ecology, Evolution, Behavior and Systematics
Abstract

Marine phytoplankton play important roles in the global ecosystem, with a limited number of cosmopolitan keystone species driving their biomass. Recent studies have revealed that many of these phytoplankton are complexes composed of sibling species, but little is known about the evolutionary processes underlying their formation. Gephyrocapsa huxleyi, a widely distributed and abundant unicellular marine planktonic algae, produces calcified scales (coccoliths), thereby significantly affects global biogeochemical cycles via sequestration of inorganic carbon. This species is composed of morphotypes defined by differing degrees of coccolith calcification, the evolutionary ecology of which remains unclear. Here, we report an integrated morphological, ecological and genomic survey across globally distributed G. huxleyi strains to reconstruct evolutionary relationships between morphotypes in relation to their habitats. While G. huxleyi has been considered a single cosmopolitan species, our analyses demonstrate that it has evolved to comprise at least three distinct species, which led us to formally revise the taxonomy of the G. huxleyi complex. Moreover, the first speciation event occurred before the onset of the last interglacial period (~140 ka), while the second followed during this interglacial. Then, further rapid diversifications occurred during the most recent ice-sheet expansion of the last glacial period and established morphotypes as dominant populations across environmental clines. These results suggest that glacial-cycle dynamics contributed to the isolation of ocean basins and the segregations of oceans fronts as extrinsic drivers of micro-evolutionary radiations in extant marine phytoplankton.

Published
2023
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8. Site U1488

Author

Rosenthal, Y., primary, Holbourn, A.E., additional, Kulhanek, D.K., additional, Aiello, I.W., additional, Babila, T.L., additional, Bayon, G., additional, Beaufort, L., additional, Bova, S.C., additional, Chun, J.-H., additional, Dang, H., additional, Drury, A.J., additional, Dunkley Jones, T., additional, Eichler, P.P.B., additional, Fernando, A.G.S., additional, Gibson, K., additional, Hatfield, R.G., additional, Johnson, D.L., additional, Kumagai, Y., additional, Li, T., additional, Linsley, B.K., additional, Meinicke, N., additional, Mountain, G.S., additional, Opdyke, B.N., additional, Pearson, P.N., additional, Poole, C.R., additional, Ravelo, A.C., additional, Sagawa, T., additional, Schmitt, A., additional, Wurtzel, J.B., additional, Xu, J., additional, Yamamoto, M., additional, and Zhang, Y.G., additional

Published
2018
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9. Expedition 363 summary

Author

Rosenthal, Y., primary, Holbourn, A.E., additional, Kulhanek, D.K., additional, Aiello, I.W., additional, Babila, T.L., additional, Bayon, G., additional, Beaufort, L., additional, Bova, S.C., additional, Chun, J.-H., additional, Dang, H., additional, Drury, A.J., additional, Dunkley Jones, T., additional, Eichler, P.P.B., additional, Fernando, A.G.S., additional, Gibson, K., additional, Hatfield, R.G., additional, Johnson, D.L., additional, Kumagai, Y., additional, Li, T., additional, Linsley, B.K., additional, Meinicke, N., additional, Mountain, G.S., additional, Opdyke, B.N., additional, Pearson, P.N., additional, Poole, C.R., additional, Ravelo, A.C., additional, Sagawa, T., additional, Schmitt, A., additional, Wurtzel, J.B., additional, Xu, J., additional, Yamamoto, M., additional, and Zhang, Y.G., additional

Published
2018
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10. Expedition 363 methods

Author

Rosenthal, Y., primary, Holbourn, A.E., additional, Kulhanek, D.K., additional, Aiello, I.W., additional, Babila, T.L., additional, Bayon, G., additional, Beaufort, L., additional, Bova, S.C., additional, Chun, J.-H., additional, Dang, H., additional, Drury, A.J., additional, Dunkley Jones, T., additional, Eichler, P.P.B., additional, Fernando, A.G.S., additional, Gibson, K., additional, Hatfield, R.G., additional, Johnson, D.L., additional, Kumagai, Y., additional, Li, T., additional, Linsley, B.K., additional, Meinicke, N., additional, Mountain, G.S., additional, Opdyke, B.N., additional, Pearson, P.N., additional, Poole, C.R., additional, Ravelo, A.C., additional, Sagawa, T., additional, Schmitt, A., additional, Wurtzel, J.B., additional, Xu, J., additional, Yamamoto, M., additional, and Zhang, Y.G., additional

Published
2018
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15. Proceedings of the VIIth International Orthnithological Congress at Amsterdam 1930

Author

International Ornithological Congress Amsterdam, Netherlands) 1930, Beaufort, L. F. De, Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Harvard University, Museum of Comparative Zoology, Ernst Mayr Library, International Ornithological Congress Amsterdam, Netherlands) 1930, Beaufort, L. F. De, and Beaufort, L. F. de (Lieven Ferdinand), 1879-1968

Subjects
Birds, Conference papers and proceedings, Congresses, Ornithology
Published
1931

16. Proceedings of the VIIth International Orthnithological Congress at Amsterdam 1930

Author

International Ornithological Congress Amsterdam, Netherlands) 1930, Beaufort, L. F. De, Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Harvard University, Museum of Comparative Zoology, Ernst Mayr Library, International Ornithological Congress Amsterdam, Netherlands) 1930, Beaufort, L. F. De, and Beaufort, L. F. de (Lieven Ferdinand), 1879-1968

Subjects
Birds, Conference papers and proceedings, Congresses, Ornithology

17. General Notes

Author

de Beaufort, L. F., Test, Frederick H., Geist, Otto William, Taylor, Walter P., Swanson, Gustav, Johnson, Charles E., Lawrence, Barbara, Bebb, William, Wright, George M., Hamilton,, W. J., Gilmore, Raymond M., Salvesen, Sigvald, and Murie, Olaus J.

Published
1934
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19. Sensitivity of coccolithophores to carbonate chemistry and ocean acidification

Author

Beaufort, L., Probert, I., de Garidel-Thoron, T., Bendif, E.M., Ruiz-Pino, D., Metzl, N., Goyet, C., Buchet, N., Coupel, P., Grelaud, M., Rost, B., Rickaby, R.E.M., and de Vargas, C.

Subjects
Water acidification -- Environmental aspects, Carbonates -- Chemical properties -- Environmental aspects, Coccolithophorids -- Chemical properties, Environmental issues, Science and technology, Zoology and wildlife conservation
Abstract

About one-third of the carbon dioxide (C[O.sub.2]) released into the atmosphere as a result of human activity has been absorbed by the oceans (1), where it partitions into the constituent ions of carbonic acid. This leads to ocean acidification, one of the major threats to marine ecosystems (2) and particularly to calcifying organisms such as corals (3,4), foraminifera (5-7) and coccolithophores (8). Coccolithophores are abundant phytoplankton that are responsible for a large part of modern oceanic carbonate production. Culture experiments investigating the physiological response of coccolithophore calcification to increased C[O.sub.2] have yielded contradictory results between and even within species (8-11). Here we quantified the calcite mass of dominant coccolithophores in the present ocean and over the past forty thousand years, and found a marked pattern of decreasing calcification with increasing partial pressure of C[O.sub.2] and concomitant decreasing concentrations of C[O.sub.3.sup.2-]. Our analyses revealed that differentially calcified species and morphotypes are distributed in the ocean according to carbonate chemistry. A substantial impact on the marine carbon cycle might be expected upon extrapolation of this correlation to predicted ocean acidification in the future. However, our discovery of a heavily calcified Emiliania huxleyi morphotype in modern waters with low pH highlights the complexity of assemblage-level responses to environmental forcing factors., To assess the influence of the environment on coccolithophore calcification, we investigated 180 surface-water and 555 sediment-core samples encompassing a wide spectrum of present and past oceanic conditions (Fig. 1). [...]

Published
2011
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22. The fishes of the Indo-Australian Archipelago ...

Author

Weber, Max, 1852-1937, Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Smithsonian Libraries, University of California Libraries (archive.org), Weber, Max, 1852-1937, and Beaufort, L. F. de (Lieven Ferdinand), 1879-1968

Subjects
Bleecker, Pieter., Fishes, Malay Archipelago, Pacific Ocean
Published
1911

24. Nova Guinea : résultats de l'expédition scientifique néerlandaise à la Nouvelle-Guinée ...

Author

Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Herderschee, A. Franssen, Lorentz, H. A. 1853-1928, Pulle, A. A. (August Adriaan), 1878-1955, Rutten, L. 1884, American Museum of Natural History Library, Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Herderschee, A. Franssen, Lorentz, H. A. 1853-1928, Pulle, A. A. (August Adriaan), 1878-1955, and Rutten, L. 1884

Subjects
Indonesia, Papua, Plants

25. The fishes of the Indo-Australian Archipelago ...

Author

Weber, Max, 1852-1937, Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Smithsonian Libraries and Archives, Weber, Max, 1852-1937, and Beaufort, L. F. de (Lieven Ferdinand), 1879-1968

Subjects
Bleecker, Pieter., Fishes, Malay Archipelago, Pacific Ocean

26. The fishes of the Indo-Australian Archipelago ...

Author

Weber, Max, 1852-1937, Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Smithsonian Libraries and Archives, Weber, Max, 1852-1937, and Beaufort, L. F. de (Lieven Ferdinand), 1879-1968

Subjects
Bleecker, Pieter., Fishes, Malay Archipelago, Pacific Ocean

27. The fishes of the Indo-Australian Archipelago ...

Author

Weber, Max, 1852-1937, Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Smithsonian Libraries and Archives, Weber, Max, 1852-1937, and Beaufort, L. F. de (Lieven Ferdinand), 1879-1968

Subjects
Bleecker, Pieter., Fishes, Malay Archipelago, Pacific Ocean

28. Nova Guinea : résultats de l'expédition scientifique néerlandaise à la Nouvelle-Guinée ...

Author

Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Herderschee, A. Franssen, Lorentz, H. A. 1853-1928, Pulle, A. A. (August Adriaan), 1878-1955, Rutten, L. 1884, New York Botanical Garden, LuEsther T. Mertz Library, Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Herderschee, A. Franssen, Lorentz, H. A. 1853-1928, Pulle, A. A. (August Adriaan), 1878-1955, and Rutten, L. 1884

Subjects
Indonesia, Papua, Plants

29. Nova Guinea : résultats de l'expédition scientifique néerlandaise à la Nouvelle-Guinée ...

Author

Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Herderschee, A. Franssen, Lorentz, H. A. 1853-1928, Pulle, A. A. (August Adriaan), 1878-1955, Rutten, L. 1884, New York Botanical Garden, LuEsther T. Mertz Library, Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Herderschee, A. Franssen, Lorentz, H. A. 1853-1928, Pulle, A. A. (August Adriaan), 1878-1955, and Rutten, L. 1884

Subjects
Indonesia, Papua, Plants

30. Nova Guinea : résultats de l'expédition scientifique néerlandaise à la Nouvelle-Guinée ...

Author

Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Herderschee, A. Franssen, Lorentz, H. A. 1853-1928, Pulle, A. A. (August Adriaan), 1878-1955, Rutten, L. 1884, New York Botanical Garden, LuEsther T. Mertz Library, Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Herderschee, A. Franssen, Lorentz, H. A. 1853-1928, Pulle, A. A. (August Adriaan), 1878-1955, and Rutten, L. 1884

Subjects
Indonesia, Papua, Plants

31. The fishes of the Indo-Australian Archipelago ...

Author

Weber, Max, 1852-1937, Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Smithsonian Libraries, Weber, Max, 1852-1937, and Beaufort, L. F. de (Lieven Ferdinand), 1879-1968

Subjects
Bleecker, Pieter., Fishes, Malay Archipelago, Pacific Ocean

32. Nova Guinea : résultats de l'expédition scientifique néerlandaise à la Nouvelle-Guinée ...

Author

Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Herderschee, A. Franssen, Lorentz, H. A. 1853-1928, Pulle, A. A. (August Adriaan), 1878-1955, Rutten, L. 1884, New York Botanical Garden, LuEsther T. Mertz Library, Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Herderschee, A. Franssen, Lorentz, H. A. 1853-1928, Pulle, A. A. (August Adriaan), 1878-1955, and Rutten, L. 1884

Subjects
Indonesia, Papua, Plants

33. Nova Guinea : résultats de l'expédition scientifique néerlandaise à la Nouvelle-Guinée ...

Author

Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Herderschee, A. Franssen, Lorentz, H. A. 1853-1928, Pulle, A. A. (August Adriaan), 1878-1955, Rutten, L. 1884, Harvard University Botany Libraries, Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Herderschee, A. Franssen, Lorentz, H. A. 1853-1928, Pulle, A. A. (August Adriaan), 1878-1955, and Rutten, L. 1884

Subjects
Indonesia, Papua, Plants

34. Nova Guinea : résultats de l'expédition scientifique néerlandaise à la Nouvelle-Guinée ...

Author

Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Herderschee, A. Franssen, Lorentz, H. A. 1853-1928, Pulle, A. A. (August Adriaan), 1878-1955, Rutten, L. 1884, Harvard University Botany Libraries, Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Herderschee, A. Franssen, Lorentz, H. A. 1853-1928, Pulle, A. A. (August Adriaan), 1878-1955, and Rutten, L. 1884

Subjects
Indonesia, Papua, Plants

35. Nova Guinea : résultats de l'expédition scientifique néerlandaise à la Nouvelle-Guinée ...

Author

Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Herderschee, A. Franssen, Lorentz, H. A. 1853-1928, Pulle, A. A. (August Adriaan), 1878-1955, Rutten, L. 1884, Harvard University Botany Libraries, Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Herderschee, A. Franssen, Lorentz, H. A. 1853-1928, Pulle, A. A. (August Adriaan), 1878-1955, and Rutten, L. 1884

Subjects
Indonesia, Papua, Plants

36. Nova Guinea : résultats de l'expédition scientifique néerlandaise à la Nouvelle-Guinée ...

Author

Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Herderschee, A. Franssen, Lorentz, H. A. 1853-1928, Pulle, A. A. (August Adriaan), 1878-1955, Rutten, L. 1884, American Museum of Natural History Library, Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Herderschee, A. Franssen, Lorentz, H. A. 1853-1928, Pulle, A. A. (August Adriaan), 1878-1955, and Rutten, L. 1884

Subjects
Indonesia, Papua, Plants

37. Nova Guinea : résultats de l'expédition scientifique néerlandaise à la Nouvelle-Guinée ...

Author

Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Herderschee, A. Franssen, Lorentz, H. A. 1853-1928, Pulle, A. A. (August Adriaan), 1878-1955, Rutten, L. 1884, American Museum of Natural History Library, Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Herderschee, A. Franssen, Lorentz, H. A. 1853-1928, Pulle, A. A. (August Adriaan), 1878-1955, and Rutten, L. 1884

Subjects
Indonesia, Papua, Plants

38. Nova Guinea : résultats de l'expédition scientifique néerlandaise à la Nouvelle-Guinée ...

Author

Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Herderschee, A. Franssen, Lorentz, H. A. 1853-1928, Pulle, A. A. (August Adriaan), 1878-1955, Rutten, L. 1884, American Museum of Natural History Library, Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Herderschee, A. Franssen, Lorentz, H. A. 1853-1928, Pulle, A. A. (August Adriaan), 1878-1955, and Rutten, L. 1884

Subjects
Indonesia, Papua, Plants

39. Nova Guinea : résultats de l'expédition scientifique néerlandaise à la Nouvelle-Guinée ...

Author

Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Herderschee, A. Franssen, Lorentz, H. A. 1853-1928, Pulle, A. A. (August Adriaan), 1878-1955, Rutten, L. 1884, American Museum of Natural History Library, Beaufort, L. F. de (Lieven Ferdinand), 1879-1968, Herderschee, A. Franssen, Lorentz, H. A. 1853-1928, Pulle, A. A. (August Adriaan), 1878-1955, and Rutten, L. 1884

Subjects
Indonesia, Papua, Plants

45. Downward particle fluxes within different productivity regimes off the Mauritanian upwelling zone (EUMELI program)

Author

Bory, A., Jeandel, C., Leblond, N., Vangriesheim, A., Khripounoff, A., Beaufort, L., Rabouille, C., Nicolas, E., Tachikawa, K., Etcheber, H., and Buat-Menard, P.

Subjects
Mauritania -- Environmental aspects, North Atlantic Ocean -- Environmental aspects, Eutrophication -- Research, Marine productivity -- Research, Upwelling (Oceanography) -- Research, Earth sciences
Abstract

Research indicates that downward particle flux in the North Atlantic Ocean, near the Mauritanian upwelling zone, is correlated with westward surface currents. These currents are likely to transport biomass-rich water masses seaward from coastal regions. Upwelling influence is strongest at the coastal mesotrophic site.

Published
2001

47. X-ray nanotomography of coccolithophores reveals that coccolith mass and segment number correlate with grid size

Author

Probert, I., Beaufort, L., Sucheras-Marx, B., Chushkin, Y., Zontone, F., Gibaud, A., and Beuvier, T.

Subjects
emiliania-huxleyi, calcification response, gephyrocapsa-oceanica, reduced calcification, diffraction, carbonate, calcite, co2, resolution, growth
Abstract

Coccolithophores of the Noelaerhabdaceae family are covered by imbricated coccoliths, each composed of multiple calcite crystals radially distributed around the periphery of a grid. The factors that determine coccolith size remain obscure. Here, we used synchrotron-based three-dimensional Coherent X-ray Diffraction Imaging to study coccoliths of 7 species of Gephyrocapsa, Emiliania and Reticulofenestra with a resolution close to 30 nm. Segmentation of 45 coccoliths revealed remarkable size, mass and segment number variations, even within single coccospheres. In particular, we observed that coccolith mass correlates with grid perimeter which scales linearly with crystal number. Our results indirectly support the idea that coccolith mass is determined in the coccolith vesicle by the size of the organic base plate scale (OBPS) around which R-unit nucleation occurs every 110-120 nm. The curvation of coccoliths allows inference of a positive correlation between cell nucleus, OBPS and coccolith sizes.

Published
2019

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