Carbon dioxide forcing alone insufficient to explain Palaeocene–Eocene Thermal Maximum warming

The Palaeocene–Eocene Thermal Maximum (PETM) was a significant global warming event in the Earth's history (approx. 55 Ma). The cause for this warming event has been linked to increases in greenhouse gases, specifically carbon dioxide and methane. This rapid warming took place in the presence of the existing Early Eocene warm climate. Given that projected business-as-usual levels of atmospheric carbon dioxide reach concentrations of 800–1100 ppmv by 2100, it is of interest to study past climates where atmospheric carbon dioxide was higher than present. This is especially the case given the difficulty of climate models in simulating past warm climates. This study explores the sensitivity of the simulated pre-PETM and PETM periods to change in cloud condensation nuclei (CCN) and microphysical properties of liquid water clouds. Assuming lower levels of CCN for both of these periods leads to significant warming, especially at high latitudes. The study indicates that past differences in cloud properties may be an important factor in accurately simulating past warm climates. Importantly, additional shortwave warming from such a mechanism would imply lower required atmospheric CO 2 concentrations for simulated surface temperatures to be in reasonable agreement with proxy data for the Eocene.

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The time lag between a carbon dioxide emission and maximum warming increases with the size of the emission

Environmental Research Letters ◽

10.1088/1748-9326/10/3/031001 ◽

2015 ◽

Vol 10 (3) ◽

pp. 031001 ◽

Cited By ~ 20

Author(s):

Kirsten Zickfeld ◽

Tyler Herrington

Keyword(s):

Carbon Dioxide ◽

Time Lag ◽

Carbon Dioxide Emission ◽

Maximum Warming

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Spatial change of precipitation in response to the Paleocene-Eocene thermal Maximum warming in China

Global and Planetary Change ◽

10.1016/j.gloplacha.2020.103313 ◽

2020 ◽

Vol 194 ◽

pp. 103313

Author(s):

Zuoling Chen ◽

Xinxin Dong ◽

Xu Wang ◽

Zihua Tang ◽

Shiling Yang ◽

...

Keyword(s):

Spatial Change ◽

Thermal Maximum ◽

Maximum Warming

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Large-scale ocean deoxygenation during the Paleocene-Eocene Thermal Maximum

Science ◽

10.1126/science.aar8658 ◽

2018 ◽

Vol 361 (6404) ◽

pp. 804-806 ◽

Cited By ~ 19

Author(s):

Weiqi Yao ◽

Adina Paytan ◽

Ulrich G. Wortmann

Keyword(s):

Carbon Dioxide ◽

Large Scale ◽

Sulfur Isotope ◽

Emission Scenario ◽

Deep Ocean ◽

Marine Species ◽

Thermal Maximum ◽

Multicellular Organisms ◽

Sulfur Isotope Data ◽

Ocean Deoxygenation

The consequences of global warming for fisheries are not well understood, but the geological record demonstrates that carbon cycle perturbations are frequently associated with ocean deoxygenation. Of particular interest is the Paleocene-Eocene Thermal Maximum (PETM), where the carbon dioxide input into the atmosphere was similar to the IPCC RCP8.5 emission scenario. Here we present sulfur-isotope data that record a positive 1 per mil excursion during the PETM. Modeling suggests that large parts of the ocean must have become sulfidic. The toxicity of hydrogen sulfide will render two of the largest and least explored ecosystems on Earth, the mesopelagic and bathypelagic zones, uninhabitable by multicellular organisms. This will affect many marine species whose ecozones stretch into the deep ocean.

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Maximum warming occurs about one decade after a carbon dioxide emission

Environmental Research Letters ◽

10.1088/1748-9326/9/12/124002 ◽

2014 ◽

Vol 9 (12) ◽

pp. 124002 ◽

Cited By ~ 70

Author(s):

Katharine L Ricke ◽

Ken Caldeira

Keyword(s):

Carbon Dioxide ◽

Carbon Dioxide Emission ◽

Maximum Warming

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Electron Cytochemical Study of Carbon Dioxide Laser Effect on Rhesus Monkey Cornea

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010005113x ◽

1974 ◽

Vol 32 ◽

pp. 224-225

Author(s):

K. C. Tsou ◽

J. Morris ◽

P. Shawaluk ◽

B. Stuck ◽

E. Beatrice

Keyword(s):

Carbon Dioxide ◽

Electron Microscope ◽

Rhesus Monkey ◽

Carbon Dioxide Laser ◽

Cytochemical Study ◽

Laser Effect

While much is known regarding the effect of lasers on the retina, little study has been done on the effect of lasers on cornea, because of the limitation of the size of the material. Using a combination of electron microscope and several newly developed cytochemical methods, the effect of laser can now be studied on eye for the purpose of correlating functional and morphological damage. The present paper illustrates such study with CO2 laser on Rhesus monkey.

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The Critical Point Drying Method Applied to Scanning Electron Microscopy of L-929 Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100068382 ◽

1970 ◽

Vol 28 ◽

pp. 278-279

Author(s):

Charles TurnbiLL ◽

Delbert E. Philpott

Keyword(s):

Electron Microscopy ◽

Carbon Dioxide ◽

Surface Tension ◽

Critical Point ◽

Freeze Drying ◽

Attractive Alternative ◽

Crystal Formation ◽

Critical Point Drying ◽

Time Required ◽

Scanning Electron

The advent of the scanning electron microscope (SCEM) has renewed interest in preparing specimens by avoiding the forces of surface tension. The present method of freeze drying by Boyde and Barger (1969) and Small and Marszalek (1969) does prevent surface tension but ice crystal formation and time required for pumping out the specimen to dryness has discouraged us. We believe an attractive alternative to freeze drying is the critical point method originated by Anderson (1951; for electron microscopy. He avoided surface tension effects during drying by first exchanging the specimen water with alcohol, amy L acetate and then with carbon dioxide. He then selected a specific temperature (36.5°C) and pressure (72 Atm.) at which carbon dioxide would pass from the liquid to the gaseous phase without the effect of surface tension This combination of temperature and, pressure is known as the "critical point" of the Liquid.

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