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The Heartbeat of the Oligocene Climate System
A 13-million-year continuous record of Oligocene climate from the equatorial Pacific reveals a pronounced “heartbeat” in the global carbon cycle and periodicity of glaciations. This heartbeatExpand
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Coupling of CO2 and Ice Sheet Stability Over Major Climate Transitions of the Last 20 Million Years
CO2 and Miocene Climate Change Atmospheric carbon dioxide is a powerful greenhouse gas believed to be one of the most important determinants of climate. Ice cores provide a detailed and direct recordExpand
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Eocene bipolar glaciation associated with global carbon cycle changes
The transition from the extreme global warmth of the early Eocene ‘greenhouse’ climate ∼55 million years ago to the present glaciated state is one of the most prominent changes in Earth's climaticExpand
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Methods and limitations of 'clumped' CO2 isotope (Delta47) analysis by gas-source isotope ratio mass spectrometry.
The geochemistry of multiply substituted isotopologues ('clumped-isotope' geochemistry) examines the abundances in natural materials of molecules, formula units or moieties that contain more than oneExpand
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Deep-Sea Temperature and Circulation Changes at the Paleocene-Eocene Thermal Maximum
A rapid increase in greenhouse gas levels is thought to have fueled global warming at the Paleocene-Eocene Thermal Maximum (PETM). Foraminiferal magnesium/calcium ratios indicate that bottom watersExpand
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The Magnitude and Duration of Late Ordovician–Early Silurian Glaciation
Carbonate isotopes reveal a link between past ocean temperatures and mass extinction. Understanding ancient climate changes is hampered by the inability to disentangle trends in ocean temperatureExpand
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Orbitally Induced Climate and Geochemical Variability Across the Oligocene/Miocene Boundary
To assess the influence of orbital-scale variations on late Oligocene to early Miocene climate and ocean chemistry, high-resolution (∼5 kyr) benthic foraminiferal carbon and oxygen isotope andExpand
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A record of bottom water temperature and seawater δ18O for the Southern Ocean over the past 440 kyr based on Mg/Ca of benthic foraminiferal Uvigerina spp
The sensitivity to temperature of Mg/Ca ratios in the shallow-infaunal benthic foraminifera Uvigerina spp. has been assessed. Core-top calibrations over ∼1–20 °C show a range in sensitivity ofExpand
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Equilibrium 13C-18O Isotope Signatures and `Clumped Isotope' Thermometry in Foraminifera and Coccoliths
Accurate constraints on past ocean temperatures and compositions are critical for documenting climate change and resolving its causes. Most proxies for temperature are not thermodynamically based,Expand
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Antarctic ice sheet sensitivity to atmospheric CO2 variations in the early to mid-Miocene
Significance New information from the ANDRILL-2A drill core and a complementary ice sheet modeling study show that polar climate and Antarctic ice sheet (AIS) margins were highly dynamic during theExpand
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