A Palaeogene perspective on climate sensitivity and methane hydrate instability
The Palaeocene-Eocene thermal maximum (PETM), a rapid global warming event and carbon-cycle perturbation of the early Palaeogene, provides a unique test of climate and carbon-cycle models as well as our understanding of sedimentary methane hydrate stability, albeit under conditions very different fr...
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ftucl:oai:eprints.ucl.ac.uk.OAI2:101395 2023-05-15T17:11:43+02:00 A Palaeogene perspective on climate sensitivity and methane hydrate instability Dunkley Jones, T Ridgwell, A Lunt, DJ Maslin, MA Schmidt, DN Valdes, PJ 2010-05-28 http://discovery.ucl.ac.uk/101395/ unknown ROYAL SOC PHILOS T R SOC A , 368 (1919) 2395 - 2415. (2010) PETM climate sensitivity methane hydrate EOCENE THERMAL MAXIMUM CARBON-ISOTOPE EXCURSION GLOBAL CARBON OXYGEN-ISOTOPE NORTH-AMERICA BIGHORN BASIN EARTH SYSTEM PALEOCENE OCEAN GAS Article 2010 ftucl 2016-01-15T02:34:56Z The Palaeocene-Eocene thermal maximum (PETM), a rapid global warming event and carbon-cycle perturbation of the early Palaeogene, provides a unique test of climate and carbon-cycle models as well as our understanding of sedimentary methane hydrate stability, albeit under conditions very different from the modern. The principal expression of the PETM in the geological record is a large and rapid negative excursion in the carbon isotopic composition of carbonates and organic matter from both marine and terrestrial environments. Palaeotemperature proxy data from across the PETM indicate a coincident increase in global surface temperatures of approximately 5-6 degrees C. Reliable estimates of atmospheric CO2 changes and global warming through past transient climate events can provide an important test of the climate sensitivities reproduced by state-of-the-art atmosphere-ocean general circulation models. Here, we synthesize the available carbon-cycle model estimates of the magnitude of the carbon input to the ocean-atmosphere-biosphere system, and the consequent atmospheric pCO(2) perturbation, through the PETM. We also review the theoretical mass balance arguments and available sedimentary evidence for the role of massive methane hydrate dissociation in this event. The plausible range of carbon mass input, approximately 4000-7000 PgC, strongly suggests a major alternative source of carbon in addition to any contribution from methane hydrates. We find that the potential range of PETM atmospheric pCO(2) 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. Article in Journal/Newspaper Methane hydrate University College London: UCL Discovery |
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University College London: UCL Discovery |
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topic |
PETM climate sensitivity methane hydrate EOCENE THERMAL MAXIMUM CARBON-ISOTOPE EXCURSION GLOBAL CARBON OXYGEN-ISOTOPE NORTH-AMERICA BIGHORN BASIN EARTH SYSTEM PALEOCENE OCEAN GAS |
spellingShingle |
PETM climate sensitivity methane hydrate EOCENE THERMAL MAXIMUM CARBON-ISOTOPE EXCURSION GLOBAL CARBON OXYGEN-ISOTOPE NORTH-AMERICA BIGHORN BASIN EARTH SYSTEM PALEOCENE OCEAN GAS Dunkley Jones, T Ridgwell, A Lunt, DJ Maslin, MA Schmidt, DN Valdes, PJ A Palaeogene perspective on climate sensitivity and methane hydrate instability |
topic_facet |
PETM climate sensitivity methane hydrate EOCENE THERMAL MAXIMUM CARBON-ISOTOPE EXCURSION GLOBAL CARBON OXYGEN-ISOTOPE NORTH-AMERICA BIGHORN BASIN EARTH SYSTEM PALEOCENE OCEAN GAS |
description |
The Palaeocene-Eocene thermal maximum (PETM), a rapid global warming event and carbon-cycle perturbation of the early Palaeogene, provides a unique test of climate and carbon-cycle models as well as our understanding of sedimentary methane hydrate stability, albeit under conditions very different from the modern. The principal expression of the PETM in the geological record is a large and rapid negative excursion in the carbon isotopic composition of carbonates and organic matter from both marine and terrestrial environments. Palaeotemperature proxy data from across the PETM indicate a coincident increase in global surface temperatures of approximately 5-6 degrees C. Reliable estimates of atmospheric CO2 changes and global warming through past transient climate events can provide an important test of the climate sensitivities reproduced by state-of-the-art atmosphere-ocean general circulation models. Here, we synthesize the available carbon-cycle model estimates of the magnitude of the carbon input to the ocean-atmosphere-biosphere system, and the consequent atmospheric pCO(2) perturbation, through the PETM. We also review the theoretical mass balance arguments and available sedimentary evidence for the role of massive methane hydrate dissociation in this event. The plausible range of carbon mass input, approximately 4000-7000 PgC, strongly suggests a major alternative source of carbon in addition to any contribution from methane hydrates. We find that the potential range of PETM atmospheric pCO(2) 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. |
format |
Article in Journal/Newspaper |
author |
Dunkley Jones, T Ridgwell, A Lunt, DJ Maslin, MA Schmidt, DN Valdes, PJ |
author_facet |
Dunkley Jones, T Ridgwell, A Lunt, DJ Maslin, MA Schmidt, DN Valdes, PJ |
author_sort |
Dunkley Jones, T |
title |
A Palaeogene perspective on climate sensitivity and methane hydrate instability |
title_short |
A Palaeogene perspective on climate sensitivity and methane hydrate instability |
title_full |
A Palaeogene perspective on climate sensitivity and methane hydrate instability |
title_fullStr |
A Palaeogene perspective on climate sensitivity and methane hydrate instability |
title_full_unstemmed |
A Palaeogene perspective on climate sensitivity and methane hydrate instability |
title_sort |
palaeogene perspective on climate sensitivity and methane hydrate instability |
publisher |
ROYAL SOC |
publishDate |
2010 |
url |
http://discovery.ucl.ac.uk/101395/ |
genre |
Methane hydrate |
genre_facet |
Methane hydrate |
op_source |
PHILOS T R SOC A , 368 (1919) 2395 - 2415. (2010) |
_version_ |
1766068490744102912 |