Abrupt reversal in ocean overturning during the Palaeocene/Eocene warm period

  title={Abrupt reversal in ocean overturning during the Palaeocene/Eocene warm period},
  author={Fl{\'a}via L. D. Nunes and Richard D. Norris},
An exceptional analogue for the study of the causes and consequences of global warming occurs at the Palaeocene/Eocene Thermal Maximum, 55 million years ago. A rapid rise of global temperatures during this event accompanied turnovers in both marine and terrestrial biota, as well as significant changes in ocean chemistry and circulation. Here we present evidence for an abrupt shift in deep-ocean circulation using carbon isotope records from fourteen sites. These records indicate that deep-ocean… 
Constraints on ocean circulation at the Paleocene–Eocene Thermal Maximum from neodymium isotopes
Abstract. Global warming during the Paleocene–Eocene Thermal Maximum (PETM)  ∼  55 million years ago (Ma) coincided with a massive release of carbon to the ocean–atmosphere system, as indicated by
CO2-driven ocean circulation changes as an amplifier of Paleocene-Eocene thermal maximum hydrate destabilization
Changes in ocean circulation have been proposed as a trigger mechanism for the large coupled climate and carbon cycle perturbations at the Paleocene-Eocene Thermal Maximum (PETM, ca. 55 Ma). An
A transient deep‐sea circulation switch during Eocene Thermal Maximum 2
Ever since its discovery, Eocene Thermal Maximum 2 (ETM2; ~53.7 Ma) has been considered as one of the “little brothers” of the Paleocene-Eocene Thermal Maximum (PETM; ~56 Ma) as it displays similar
Persistent environmental change after the Paleocene–Eocene Thermal Maximum in the eastern North Atlantic
Modelling the carbon cycle during the Paleocene-Eocene thermal maximum
The Paleocene-Eocene Thermal Maximum (PETM, ∼56 million years ago) was a transient global warming event, characterized by a prominent negative carbon isotope excursion (CIE) in the proxy record, most
Paleocene-Eocene Thermal Maximum: Implications for the benthic extinction Global decline in ocean ventilation, oxygenation, and productivity during the
ABSTRACTThe prominent global warming event at the Paleocene-Eocene boundary (55 Ma), referred to as the Paleocene-Eocene Thermal Maximum (PETM), was characterized by rapid temperature increase and
A Palaeogene perspective on climate sensitivity and methane hydrate instability
It is found that the potential range of PETM atmospheric pCO2 increase, combined with proxy estimates of the PETM temperature anomaly, does not necessarily imply climate sensitivities beyond the range of state-of-the-art climate models.


Termination of global warmth at the Palaeocene/Eocene boundary through productivity feedback
The unusually rapid return of δ13C to values similar to those before the methane release and the apparent coupling of the accumulation rates of biogenic barium to temperature, suggests that the enhanced deposition of organic matter to the deep sea may have efficiently cooled this greenhouse climate by the rapid removal of excess carbon dioxide from the atmosphere.
Could changing ocean circulation have destabilized methane hydrate at the Paleocene/Eocene boundary?
[1] During the Paleocene-Eocene Thermal Maximum (PETM, ∼55 Ma), marine and terrestrial carbon isotope values exhibit a negative shift of at least 2.5‰, indicative of massive destabilization of marine
Numerical evidence against reversed thermohaline circulation in the warm Paleocene/Eocene ocean
The question of whether deep water formation might have occurred in subtropical lati- tudes in the early Cenozoic is examined through use of a global ocean model forced by mixed boundary conditions.
Carbon cycling and chronology of climate warming during the Palaeocene/Eocene transition
Current models of the global carbon cycle lack natural mechanisms to explain known large, transient shifts in past records of the stable carbon-isotope ratio (δ13C) of carbon reservoirs. The
Paleocene to Eocene benthic foraminiferal isotopes and assemblages: Implications for deepwater circulation
Early Paleogene warm climates may have been linked to different modes and sources of deepwater formation. Warm polar temperatures of the Paleocene and Eocene may have resulted from either increased
Abrupt deep-sea warming, palaeoceanographic changes and benthic extinctions at the end of the Palaeocene
A remarkable oxygen and carbon isotope excursion occurred in Antarctic waters near the end of the Palaeocene (~57.33 Myr ago), indicating rapid global warming and oceanographic changes that caused
New chronology for the late Paleocene thermal maximum and its environmental implications
The late Paleocene thermal maximum (LPTM) is associated with a brief, but intense, interval of global warming and a massive perturbation of the global carbon cycle. We have developed a new orbital
A humid climate state during the Palaeocene/Eocene thermal maximum
The authors' results provide evidence for a previously unrecognized discrete shift in the state of the climate system during the PETM, characterized by large increases in mid-latitude tropospheric humidity and enhanced cycling of carbon through terrestrial ecosystems.
Rapid Acidification of the Ocean During the Paleocene-Eocene Thermal Maximum
Geochemical data from five new South Atlantic deep-sea sections indicate that a large mass of carbon dissolved in the ocean at the Paleocene-Eocene boundary and that permanent sequestration of this carbon occurred through silicate weathering feedback.