Episodic fresh surface waters in the Eocene Arctic Ocean

@article{Brinkhuis2006EpisodicFS,
  title={Episodic fresh surface waters in the Eocene Arctic Ocean},
  author={Henk Brinkhuis and Stefan Schouten and Margaret E. Collinson and Appy Sluijs and Jaap S. Sinninghe Damst{\'e} and Gerald R. Dickens and Matthew Huber and Thomas M. Cronin and Jonaotaro Onodera and Kozo Takahashi and Jonathan P. Bujak and Ruediger Stein and Johan van der Burgh and James S. Eldrett and Ian C. Harding and Andr{\'e} F. Lotter and Francesca Sangiorgi and Han van Konijnenburg-van Cittert and Jan W. De Leeuw and Jens Matthiessen and Jan Backman and Kathryn Moran},
  journal={Nature},
  year={2006},
  volume={441},
  pages={606-609}
}
It has been suggested, on the basis of modern hydrology and fully coupled palaeoclimate simulations, that the warm greenhouse conditions that characterized the early Palaeogene period (55–45 Myr ago) probably induced an intensified hydrological cycle with precipitation exceeding evaporation at high latitudes. Little field evidence, however, has been available to constrain oceanic conditions in the Arctic during this period. Here we analyse Palaeogene sediments obtained during the Arctic Coring… 

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References

SHOWING 1-10 OF 35 REFERENCES
Subtropical Arctic Ocean temperatures during the Palaeocene/Eocene thermal maximum
TLDR
It is shown that sea surface temperatures near the North Pole increased from ∼18 °C to over 23‬°C during this event, which suggests that higher-than-modern greenhouse gas concentrations must have operated in conjunction with other feedback mechanisms—perhaps polar stratospheric clouds or hurricane-induced ocean mixing—to amplify early Palaeogene polar temperatures.
The Cenozoic palaeoenvironment of the Arctic Ocean
TLDR
This record of the Neogene reveals cooling of the Arctic that was synchronous with the expansion of Greenland ice and East Antarctic ice and supporting arguments for bipolar symmetry in climate change.
Oxygen isotope and paleobotanical estimates of temperature and δ18O–latitude gradients over North America during the early Eocene
Empirical estimates of climate parameters such as mean annual tempera- ture (MAT) are essential to describe both ancient climate and to ground truth climate model simulations of past climates. In
Humidity estimate for the middle Eocene Arctic rain forest
The exquisite preservation of fossilized Metasequoia trees that grew near 808N latitude during the middle Eocene (ca. 45 Ma) in Nunavut, Canada, allowed for dD and d 18 O analyses of cellulose,
Eocene continental climates and latitudinal temperature gradients
Global climate during the Mesozoic and early Cenozoic is thought to have been warmer than at present, but there is debate about winter temperatures. Paleontological data indicate mild temperatures
Atmospheric carbon dioxide concentrations over the past 60 million years
TLDR
The boron-isotope ratios of ancient planktonic foraminifer shells are used to estimate the pH of surface-layer sea water throughout the past 60 million years, which can be used to reconstruct atmospheric CO2 concentrations.
...
1
2
3
4
...