Articles | Volume 14, issue 10
https://doi.org/10.5194/cp-14-1515-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/cp-14-1515-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
22 Oct 2018
Research article |
| 22 Oct 2018
| 22 Oct 2018
Reduced carbon cycle resilience across the Palaeocene–Eocene Thermal Maximum
David I. Armstrong McKay
CORRESPONDING AUTHOR
Ocean and Earth Science, University of Southampton, National
Oceanography Centre Southampton, Southampton, SO14 3ZY, UK
Stockholm Resilience Centre, Stockholm University,
Kräftriket 2B, 10691 Stockholm, Sweden
Timothy M. Lenton
Earth System Science group, College of Life and Environmental
Sciences, University of Exeter, Exeter, EX4 4QE, UK
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Vasilis Dakos, Chris A. Boulton, Joshua E. Buxton, Jesse F. Abrams, Beatriz Arellano-Nava, David I. Armstrong McKay, Sebastian Bathiany, Lana Blaschke, Niklas Boers, Daniel Dylewsky, Carlos López-Martínez, Isobel Parry, Paul Ritchie, Bregje van der Bolt, Larissa van der Laan, Els Weinans, and Sonia Kéfi
Earth Syst. Dynam., 15, 1117–1135, https://doi.org/10.5194/esd-15-1117-2024, https://doi.org/10.5194/esd-15-1117-2024, 2024
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Tipping points are abrupt, rapid, and sometimes irreversible changes, and numerous approaches have been proposed to detect them in advance. Such approaches have been termed early warning signals and represent a set of methods for identifying changes in the underlying behaviour of a system across time or space that might indicate an approaching tipping point. Here, we review the literature to explore where, how, and which early warnings have been used in real-world case studies so far.
Dag O. Hessen, Tom Andersen, David Armstrong McKay, Sarian Kosten, Mariana Meerhoff, Amy Pickard, and Bryan M. Spears
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Lakes worldwide are changing and under threat due to stressors such as overload of nutrients, increased input of organic carbon (“browning”), and climate change, which may cause reduced water volume, salinization, or even loss of waterbodies. Some of these changes are abrupt to the extent that they can be characterized as tipping points for that particular system. Such changes may also cause increased release of greenhouse gases, and lakes are major players in the global climate in this context.
Sina Loriani, Yevgeny Aksenov, David Armstrong McKay, Govindasamy Bala, Andreas Born, Cristiano M. Chiessi, Henk Dijkstra, Jonathan F. Donges, Sybren Drijfhout, Matthew H. England, Alexey V. Fedorov, Laura Jackson, Kai Kornhuber, Gabriele Messori, Francesco Pausata, Stefanie Rynders, Jean-Baptiste Salée, Bablu Sinha, Steven Sherwood, Didier Swingedouw, and Thejna Tharammal
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In this work, we draw on paleoreords, observations and modelling studies to review tipping points in the ocean overturning circulations, monsoon systems and global atmospheric circulations. We find indications for tipping in the ocean overturning circulations and the West African monsoon, with potentially severe impacts on the Earth system and humans. Tipping in the other considered systems is considered conceivable but currently not sufficiently supported by evidence.
David I. Armstrong McKay, Sarah E. Cornell, Katherine Richardson, and Johan Rockström
Earth Syst. Dynam., 12, 797–818, https://doi.org/10.5194/esd-12-797-2021, https://doi.org/10.5194/esd-12-797-2021, 2021
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We use an Earth system model with two new ocean ecosystem features (plankton size traits and temperature-sensitive nutrient recycling) to revaluate the effect of climate change on sinking organic carbon (the
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Mark S. Williamson and Timothy M. Lenton
Earth Syst. Dynam., 15, 1483–1508, https://doi.org/10.5194/esd-15-1483-2024, https://doi.org/10.5194/esd-15-1483-2024, 2024
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Climate models have transitioned to a superrotating atmospheric state under a broad range of warm climates. Such a transition would change global weather patterns should it occur. Here we simulate this transition using an idealized climate model and look for any early warnings of the superrotating state before it happens. We find several early warning indicators that we attribute to an oscillating pattern in the windfield fluctuations.
Vasilis Dakos, Chris A. Boulton, Joshua E. Buxton, Jesse F. Abrams, Beatriz Arellano-Nava, David I. Armstrong McKay, Sebastian Bathiany, Lana Blaschke, Niklas Boers, Daniel Dylewsky, Carlos López-Martínez, Isobel Parry, Paul Ritchie, Bregje van der Bolt, Larissa van der Laan, Els Weinans, and Sonia Kéfi
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Tipping points are abrupt, rapid, and sometimes irreversible changes, and numerous approaches have been proposed to detect them in advance. Such approaches have been termed early warning signals and represent a set of methods for identifying changes in the underlying behaviour of a system across time or space that might indicate an approaching tipping point. Here, we review the literature to explore where, how, and which early warnings have been used in real-world case studies so far.
Sibel Eker, Timothy M. Lenton, Tom Powell, Jürgen Scheffran, Steven R. Smith, Deepthi Swamy, and Caroline Zimm
Earth Syst. Dynam., 15, 789–800, https://doi.org/10.5194/esd-15-789-2024, https://doi.org/10.5194/esd-15-789-2024, 2024
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Cascading effects through cross-system interactions are one of the biggest promises of positive tipping points to create rapid climate and sustainability action. Here, we review these in terms of their interactions with sociotechnical systems such as energy, transport, agriculture, society, and policy.
Dag O. Hessen, Tom Andersen, David Armstrong McKay, Sarian Kosten, Mariana Meerhoff, Amy Pickard, and Bryan M. Spears
Earth Syst. Dynam., 15, 653–669, https://doi.org/10.5194/esd-15-653-2024, https://doi.org/10.5194/esd-15-653-2024, 2024
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Lakes worldwide are changing and under threat due to stressors such as overload of nutrients, increased input of organic carbon (“browning”), and climate change, which may cause reduced water volume, salinization, or even loss of waterbodies. Some of these changes are abrupt to the extent that they can be characterized as tipping points for that particular system. Such changes may also cause increased release of greenhouse gases, and lakes are major players in the global climate in this context.
Sina Loriani, Yevgeny Aksenov, David Armstrong McKay, Govindasamy Bala, Andreas Born, Cristiano M. Chiessi, Henk Dijkstra, Jonathan F. Donges, Sybren Drijfhout, Matthew H. England, Alexey V. Fedorov, Laura Jackson, Kai Kornhuber, Gabriele Messori, Francesco Pausata, Stefanie Rynders, Jean-Baptiste Salée, Bablu Sinha, Steven Sherwood, Didier Swingedouw, and Thejna Tharammal
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In this work, we draw on paleoreords, observations and modelling studies to review tipping points in the ocean overturning circulations, monsoon systems and global atmospheric circulations. We find indications for tipping in the ocean overturning circulations and the West African monsoon, with potentially severe impacts on the Earth system and humans. Tipping in the other considered systems is considered conceivable but currently not sufficiently supported by evidence.
Antony Philip Emenyu, Thomas Pienkowski, Andrew M. Cunliffe, Timothy M. Lenton, and Tom Powell
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This paper explores what processes could boost adoption rates for regenerative agriculture programs in Africa and draws on insights from successful rapid scaling of TIST in east Africa. Found that the cultivation of reinforcing feedback processes that strengthened the social capital around adoption and elimination of barriers to carbon accreditation for RA projects to be key success factors and possible opportunities new and ongoing RA programs to boost their adoption rates.
Stephen P. Hesselbo, Aisha Al-Suwaidi, Sarah J. Baker, Giorgia Ballabio, Claire M. Belcher, Andrew Bond, Ian Boomer, Remco Bos, Christian J. Bjerrum, Kara Bogus, Richard Boyle, James V. Browning, Alan R. Butcher, Daniel J. Condon, Philip Copestake, Stuart Daines, Christopher Dalby, Magret Damaschke, Susana E. Damborenea, Jean-Francois Deconinck, Alexander J. Dickson, Isabel M. Fendley, Calum P. Fox, Angela Fraguas, Joost Frieling, Thomas A. Gibson, Tianchen He, Kat Hickey, Linda A. Hinnov, Teuntje P. Hollaar, Chunju Huang, Alexander J. L. Hudson, Hugh C. Jenkyns, Erdem Idiz, Mengjie Jiang, Wout Krijgsman, Christoph Korte, Melanie J. Leng, Timothy M. Lenton, Katharina Leu, Crispin T. S. Little, Conall MacNiocaill, Miguel O. Manceñido, Tamsin A. Mather, Emanuela Mattioli, Kenneth G. Miller, Robert J. Newton, Kevin N. Page, József Pálfy, Gregory Pieńkowski, Richard J. Porter, Simon W. Poulton, Alberto C. Riccardi, James B. Riding, Ailsa Roper, Micha Ruhl, Ricardo L. Silva, Marisa S. Storm, Guillaume Suan, Dominika Szűcs, Nicolas Thibault, Alfred Uchman, James N. Stanley, Clemens V. Ullmann, Bas van de Schootbrugge, Madeleine L. Vickers, Sonja Wadas, Jessica H. Whiteside, Paul B. Wignall, Thomas Wonik, Weimu Xu, Christian Zeeden, and Ke Zhao
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Chris A. Boulton, Joshua E. Buxton, and Timothy M. Lenton
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Jakob Emanuel Deutloff, Hermann Held, and Timothy Michael Lenton
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We investigate the probabilities of triggering climate tipping points under various emission scenarios and how they are altered by additional carbon emissions from tipping points within the Earth's carbon cycle. We find that even “middle of the road” emission scenarios are highly unsafe with regard to triggering climate tipping points. Under such scenarios, probabilities of triggering are increased substantially by carbon emissions from tipping points within the Earth's carbon cycle.
Taylor Smith, Ruxandra-Maria Zotta, Chris A. Boulton, Timothy M. Lenton, Wouter Dorigo, and Niklas Boers
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Thomas S. Ball, Naomi E. Vaughan, Thomas W. Powell, Andrew Lovett, and Timothy M. Lenton
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David I. Armstrong McKay, Sarah E. Cornell, Katherine Richardson, and Johan Rockström
Earth Syst. Dynam., 12, 797–818, https://doi.org/10.5194/esd-12-797-2021, https://doi.org/10.5194/esd-12-797-2021, 2021
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We use an Earth system model with two new ocean ecosystem features (plankton size traits and temperature-sensitive nutrient recycling) to revaluate the effect of climate change on sinking organic carbon (the
biological pump) and the ocean carbon sink. These features lead to contrary pump responses to warming, with a combined effect of a smaller sink despite a more resilient pump. These results show the importance of including ecological dynamics in models for understanding climate feedbacks.
Elisa Lovecchio and Timothy M. Lenton
Geosci. Model Dev., 13, 1865–1883, https://doi.org/10.5194/gmd-13-1865-2020, https://doi.org/10.5194/gmd-13-1865-2020, 2020
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Emma W. Littleton, Anna B. Harper, Naomi E. Vaughan, Rebecca J. Oliver, Maria Carolina Duran-Rojas, and Timothy M. Lenton
Geosci. Model Dev., 13, 1123–1136, https://doi.org/10.5194/gmd-13-1123-2020, https://doi.org/10.5194/gmd-13-1123-2020, 2020
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Sebastian Bathiany, Bregje van der Bolt, Mark S. Williamson, Timothy M. Lenton, Marten Scheffer, Egbert H. van Nes, and Dirk Notz
The Cryosphere, 10, 1631–1645, https://doi.org/10.5194/tc-10-1631-2016, https://doi.org/10.5194/tc-10-1631-2016, 2016
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We examine if a potential "tipping point" in Arctic sea ice, causing abrupt and irreversible sea-ice loss, could be foreseen with statistical early warning signals. We assess this idea by using several models of different complexity. We find robust and consistent trends in variability that are not specific to the existence of a tipping point. While this makes an early warning impossible, it allows to estimate sea-ice variability from only short observational records or reconstructions.
Timothy M. Lenton, Peter-Paul Pichler, and Helga Weisz
Earth Syst. Dynam., 7, 353–370, https://doi.org/10.5194/esd-7-353-2016, https://doi.org/10.5194/esd-7-353-2016, 2016
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We identify six past revolutions in energy input and material cycling in Earth and human history. We find that human energy use has now reached a magnitude comparable to the biosphere, and conclude that a prospective sustainability revolution will require scaling up new solar energy technologies and the development of much more efficient material recycling systems. Our work was inspired by recognising the connections between Earth system science and industrial ecology at the "LOOPS" workshop.
Mark S. Williamson, Sebastian Bathiany, and Timothy M. Lenton
Earth Syst. Dynam., 7, 313–326, https://doi.org/10.5194/esd-7-313-2016, https://doi.org/10.5194/esd-7-313-2016, 2016
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We find early warnings of abrupt changes in complex dynamical systems such as the climate where the usual early warning indicators do not work. In particular, these are systems that are periodically forced, for example by the annual cycle of solar insolation. We show these indicators are good theoretically in a general setting then apply them to a specific system, that of the Arctic sea ice, which has been conjectured to be close to such a tipping point. We do not find evidence of it.
Z. A. Thomas, F. Kwasniok, C. A. Boulton, P. M. Cox, R. T. Jones, T. M. Lenton, and C. S. M. Turney
Clim. Past, 11, 1621–1633, https://doi.org/10.5194/cp-11-1621-2015, https://doi.org/10.5194/cp-11-1621-2015, 2015
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Using a combination of speleothem records and model simulations of the East Asian Monsoon over the penultimate glacial cycle, we search for early warning signals of past tipping points. We detect a characteristic slower response to perturbations prior to an abrupt monsoon shift at the glacial termination; however, we do not detect these signals in the preceding shifts. Our results have important implications for detecting tipping points in palaeoclimate records outside glacial terminations.
G. Colbourn, A. Ridgwell, and T. M. Lenton
Geosci. Model Dev., 6, 1543–1573, https://doi.org/10.5194/gmd-6-1543-2013, https://doi.org/10.5194/gmd-6-1543-2013, 2013
V. N. Livina and T. M. Lenton
The Cryosphere, 7, 275–286, https://doi.org/10.5194/tc-7-275-2013, https://doi.org/10.5194/tc-7-275-2013, 2013
Related subject area
Subject: Carbon Cycle | Archive: Marine Archives | Timescale: Cenozoic
Variations in the biological pump throughout the Miocene: evidence from organic carbon burial in Pacific Ocean sediments
Precise dating of deglacial Laptev Sea sediments via 14C and authigenic 10Be∕9Be – assessing local 14C reservoir ages
Late Eocene to early Oligocene productivity events in the proto-Southern Ocean and correlation to climate change
Tracing North Atlantic volcanism and seaway connectivity across the Paleocene–Eocene Thermal Maximum (PETM)
Late Paleocene CO2 drawdown, climatic cooling and terrestrial denudation in the southwest Pacific
Late Miocene to Holocene high-resolution eastern equatorial Pacific carbonate records: stratigraphy linked by dissolution and paleoproductivity
Glacial CO2 decrease and deep-water deoxygenation by iron fertilization from glaciogenic dust
Tropical Atlantic climate and ecosystem regime shifts during the Paleocene–Eocene Thermal Maximum
Ocean carbon cycling during the past 130 000 years – a pilot study on inverse palaeoclimate record modelling
Major perturbations in the global carbon cycle and photosymbiont-bearing planktic foraminifera during the early Eocene
Stable isotope and calcareous nannofossil assemblage record of the late Paleocene and early Eocene (Cicogna section)
Frequency, magnitude and character of hyperthermal events at the onset of the Early Eocene Climatic Optimum
Astronomical calibration of the geological timescale: closing the middle Eocene gap
Early Paleogene variations in the calcite compensation depth: new constraints using old borehole sediments from across Ninetyeast Ridge, central Indian Ocean
A seasonality trigger for carbon injection at the Paleocene–Eocene Thermal Maximum
Down the Rabbit Hole: toward appropriate discussion of methane release from gas hydrate systems during the Paleocene-Eocene thermal maximum and other past hyperthermal events
Southern ocean warming, sea level and hydrological change during the Paleocene-Eocene thermal maximum
Perturbing phytoplankton: response and isotopic fractionation with changing carbonate chemistry in two coccolithophore species
Mitchell Lyle and Annette Olivarez Lyle
Clim. Past, 20, 2685–2700, https://doi.org/10.5194/cp-20-2685-2024, https://doi.org/10.5194/cp-20-2685-2024, 2024
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Greenhouse gases were key in maintaining past warm intervals, but feedbacks are needed to sustain high atmospheric CO2 levels. We assess whether changes in the ocean degradation depth of plankton-produced organic matter (particulate organic carbon – POC) affect ocean carbon storage. Limited POC burial in sediments during the Miocene Climate Optimum (MCO) warm interval, relative to recent periods, suggests poorer POC transfer to the abyss, leading to the MCO's higher atmospheric CO2 levels.
Arnaud Nicolas, Gesine Mollenhauer, Johannes Lachner, Konstanze Stübner, Maylin Malter, Jutta Wollenburg, Hendrik Grotheer, and Florian Adolphi
Clim. Past, 20, 2617–2628, https://doi.org/10.5194/cp-20-2617-2024, https://doi.org/10.5194/cp-20-2617-2024, 2024
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We use the authigenic 10Be/9Be record of a Laptev Sea sediment core for the period 8–14 kyr BP and synchronize it with the 10Be records from absolutely dated ice cores. We employed a likelihood function to calculate the ΔR values. A benthic ΔR value of +345±60 14C years was estimated, which corresponds to a marine reservoir age of 848±90 14C years. This new ΔR value was used to refine the age–depth model for core PS2458-4, establishing it as a potential reference chronology for the Laptev Sea.
Gabrielle Rodrigues de Faria, David Lazarus, Johan Renaudie, Jessica Stammeier, Volkan Özen, and Ulrich Struck
Clim. Past, 20, 1327–1348, https://doi.org/10.5194/cp-20-1327-2024, https://doi.org/10.5194/cp-20-1327-2024, 2024
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Export productivity is part of the global carbon cycle, influencing the climate system via biological pump. About 34 million years ago, the Earth's climate experienced a climate transition from a greenhouse state to an icehouse state with the onset of ice sheets in Antarctica. Our study shows important productivity events in the Southern Ocean preceding this climatic shift. Our findings strongly indicate that the biological pump potentially played an important role in that past climate change.
Morgan T. Jones, Ella W. Stokke, Alan D. Rooney, Joost Frieling, Philip A. E. Pogge von Strandmann, David J. Wilson, Henrik H. Svensen, Sverre Planke, Thierry Adatte, Nicolas Thibault, Madeleine L. Vickers, Tamsin A. Mather, Christian Tegner, Valentin Zuchuat, and Bo P. Schultz
Clim. Past, 19, 1623–1652, https://doi.org/10.5194/cp-19-1623-2023, https://doi.org/10.5194/cp-19-1623-2023, 2023
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There are periods in Earth’s history when huge volumes of magma are erupted at the Earth’s surface. The gases released from volcanic eruptions and from sediments heated by the magma are believed to have caused severe climate changes in the geological past. We use a variety of volcanic and climatic tracers to assess how the North Atlantic Igneous Province (56–54 Ma) affected the oceans and atmosphere during a period of extreme global warming.
Christopher J. Hollis, Sebastian Naeher, Christopher D. Clowes, B. David A. Naafs, Richard D. Pancost, Kyle W. R. Taylor, Jenny Dahl, Xun Li, G. Todd Ventura, and Richard Sykes
Clim. Past, 18, 1295–1320, https://doi.org/10.5194/cp-18-1295-2022, https://doi.org/10.5194/cp-18-1295-2022, 2022
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Previous studies of Paleogene greenhouse climates identified short-lived global warming events, termed hyperthermals, that provide insights into global warming scenarios. Within the same time period, we have identified a short-lived cooling event in the late Paleocene, which we term a hypothermal, that has potential to provide novel insights into the feedback mechanisms at work in a greenhouse climate.
Mitchell Lyle, Anna Joy Drury, Jun Tian, Roy Wilkens, and Thomas Westerhold
Clim. Past, 15, 1715–1739, https://doi.org/10.5194/cp-15-1715-2019, https://doi.org/10.5194/cp-15-1715-2019, 2019
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Ocean sediment records document changes in Earth’s carbon cycle and ocean productivity. We present 8 Myr CaCO3 and bulk sediment records from seven eastern Pacific scientific drill sites to identify intervals of excess CaCO3 dissolution (high carbon storage in the oceans) and excess burial of plankton hard parts indicating high productivity. We define the regional extent of production intervals and explore the impact of the closure of the Atlantic–Pacific Panama connection on CaCO3 burial.
Akitomo Yamamoto, Ayako Abe-Ouchi, Rumi Ohgaito, Akinori Ito, and Akira Oka
Clim. Past, 15, 981–996, https://doi.org/10.5194/cp-15-981-2019, https://doi.org/10.5194/cp-15-981-2019, 2019
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Proxy records of glacial oxygen change provide constraints on the contribution of the biological pump to glacial CO2 decrease. Here, we report our numerical simulation which successfully reproduces records of glacial oxygen changes and shows the significance of iron supply from glaciogenic dust. Our model simulations clarify that the enhanced efficiency of the biological pump is responsible for glacial CO2 decline of more than 30 ppm and approximately half of deep-ocean deoxygenation.
Joost Frieling, Gert-Jan Reichart, Jack J. Middelburg, Ursula Röhl, Thomas Westerhold, Steven M. Bohaty, and Appy Sluijs
Clim. Past, 14, 39–55, https://doi.org/10.5194/cp-14-39-2018, https://doi.org/10.5194/cp-14-39-2018, 2018
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Past periods of rapid global warming such as the Paleocene–Eocene Thermal Maximum are used to study biotic response to climate change. We show that very high peak PETM temperatures in the tropical Atlantic (~ 37 ºC) caused heat stress in several marine plankton groups. However, only slightly cooler temperatures afterwards allowed highly diverse plankton communities to bloom. This shows that tropical plankton communities may be susceptible to extreme warming, but may also recover rapidly.
Christoph Heinze, Babette A. A. Hoogakker, and Arne Winguth
Clim. Past, 12, 1949–1978, https://doi.org/10.5194/cp-12-1949-2016, https://doi.org/10.5194/cp-12-1949-2016, 2016
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Sensitivities of sediment tracers to changes in carbon cycle parameters were determined with a global ocean model. The sensitivities were combined with sediment and ice core data. The results suggest a drawdown of the sea surface temperature by 5 °C, an outgassing of the land biosphere by 430 Pg C, and a strengthening of the vertical carbon transfer by biological processes at the Last Glacial Maximum. A glacial change in marine calcium carbonate production can neither be proven nor rejected.
Valeria Luciani, Gerald R. Dickens, Jan Backman, Eliana Fornaciari, Luca Giusberti, Claudia Agnini, and Roberta D'Onofrio
Clim. Past, 12, 981–1007, https://doi.org/10.5194/cp-12-981-2016, https://doi.org/10.5194/cp-12-981-2016, 2016
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The symbiont-bearing planktic foraminiferal genera Morozovella and Acarinina were among the most important calcifiers of the early Paleogene tropical and subtropical oceans. However, a remarkable and permanent switch in the relative abundance of these genera happened in the early Eocene. We show that this switch occurred at low-latitude sites near the start of the Early Eocene Climatic Optimum (EECO), a multi-million-year interval when Earth surface temperatures reached their Cenozoic maximum.
Claudia Agnini, David J. A. Spofforth, Gerald R. Dickens, Domenico Rio, Heiko Pälike, Jan Backman, Giovanni Muttoni, and Edoardo Dallanave
Clim. Past, 12, 883–909, https://doi.org/10.5194/cp-12-883-2016, https://doi.org/10.5194/cp-12-883-2016, 2016
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In this paper we present records of stable C and O isotopes, CaCO3 content, and changes in calcareous nannofossil assemblages in a upper Paleocene-lower Eocene rocks now exposed in northeast Italy. Modifications of nannoplankton assemblages and carbon isotopes are strictly linked one to each other and always display the same ranking and spacing. The integration of this two data sets represents a significative improvement in our capacity to correlate different sections at a very high resolution.
V. Lauretano, K. Littler, M. Polling, J. C. Zachos, and L. J. Lourens
Clim. Past, 11, 1313–1324, https://doi.org/10.5194/cp-11-1313-2015, https://doi.org/10.5194/cp-11-1313-2015, 2015
Short summary
Short summary
Several episodes of global warming took place during greenhouse conditions in the early Eocene and are recorded in deep-sea sediments. The stable carbon and oxygen isotope records are used to investigate the magnitude of six of these events describing their effects on the global carbon cycle and the associated temperature response. Findings indicate that these events share a common nature and hint to the presence of multiple sources of carbon release.
T. Westerhold, U. Röhl, T. Frederichs, S. M. Bohaty, and J. C. Zachos
Clim. Past, 11, 1181–1195, https://doi.org/10.5194/cp-11-1181-2015, https://doi.org/10.5194/cp-11-1181-2015, 2015
Short summary
Short summary
Testing hypotheses for mechanisms and dynamics of past climate change relies on the accuracy of geological dating. Development of a highly accurate geological timescale for the Cenozoic Era has previously been hampered by discrepancies between radioisotopic and astronomical dating methods, as well as a stratigraphic gap in the middle Eocene. We close this gap and provide a fundamental advance in establishing a reliable and highly accurate geological timescale for the last 66 million years.
B. S. Slotnick, V. Lauretano, J. Backman, G. R. Dickens, A. Sluijs, and L. Lourens
Clim. Past, 11, 473–493, https://doi.org/10.5194/cp-11-473-2015, https://doi.org/10.5194/cp-11-473-2015, 2015
J. S. Eldrett, D. R. Greenwood, M. Polling, H. Brinkhuis, and A. Sluijs
Clim. Past, 10, 759–769, https://doi.org/10.5194/cp-10-759-2014, https://doi.org/10.5194/cp-10-759-2014, 2014
G. R. Dickens
Clim. Past, 7, 831–846, https://doi.org/10.5194/cp-7-831-2011, https://doi.org/10.5194/cp-7-831-2011, 2011
A. Sluijs, P. K. Bijl, S. Schouten, U. Röhl, G.-J. Reichart, and H. Brinkhuis
Clim. Past, 7, 47–61, https://doi.org/10.5194/cp-7-47-2011, https://doi.org/10.5194/cp-7-47-2011, 2011
R. E. M. Rickaby, J. Henderiks, and J. N. Young
Clim. Past, 6, 771–785, https://doi.org/10.5194/cp-6-771-2010, https://doi.org/10.5194/cp-6-771-2010, 2010
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Short summary
This study uses statistical analyses to look for signs of declining resilience (i.e. greater sensitivity to small shocks) in the global carbon cycle and climate system across the Palaeocene–Eocene Thermal Maximum (PETM), a global warming event 56 Myr ago driven by rapid carbon release. Our main finding is that carbon cycle resilience declined in the 1.5 Myr beforehand (a time of significant volcanic emissions), which is consistent with but not proof of a carbon release tipping point at the PETM.
This study uses statistical analyses to look for signs of declining resilience (i.e. greater...
