| Title: |
Clumped isotope evidence for Early Jurassic extreme polar warmth and high climate sensitivity |
| Authors: |
Letulle, Thomas; Suan, Guillaume; Daëron, Mathieu; Rogov, Mikhail; Lécuyer, Christophe; Vinçon-Laugier, Arnauld; Reynard, Bruno; Montagnac, Gilles; Lutikov, Oleg; Schlögl, Jan |
| Contributors: |
Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE); École normale supérieure de Lyon (ENS de Lyon); Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL); Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS); Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE); Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)); Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA); Paléocéanographie (PALEOCEAN); Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)); Geological Institute of the Russian Academy of Sciences; Russian Academy of Sciences Moscow (RAS); Comenius University in Bratislava; ANR-18-CE31-0020,Oxymore,Rapports isotopiques de l'oxygène des océans mésozoïques revisités(2018) |
| Source: |
ISSN: 1814-9324. |
| Publisher Information: |
CCSD; European Geosciences Union (EGU) [2005-.] |
| Publication Year: |
2022 |
| Collection: |
Université de Versailles Saint-Quentin-en-Yvelines: HAL-UVSQ |
| Subject Terms: |
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces; environment |
| Description: |
International audience ; Periods of high atmospheric CO 2 levels during the Cretaceous-early Paleogene (∼ 140 to 34 Myr ago) were marked by very high polar temperatures and reduced latitudinal gradients relative to the Holocene. These features represent a challenge for most climate models, implying either higher-than-predicted climate sensitivity to atmospheric CO 2 or systematic biases or misinterpretations in proxy data. Here, we present a reconstruction of marine temperatures at polar (> 80 •) and middle (∼ 40 •) paleolatitudes during the Early Jurassic (∼ 180 Myr ago) based on the clumped isotope (47) and oxygen isotope (δ 18 O c) analyses of shallow buried pristine mollusc shells. Reconstructed calcification temperatures range from ∼ 8 to ∼ 18 • C in the Toarcian Arctic and from ∼ 24 to ∼ 28 • C in Pliensbachian midpaleolatitudes. These polar temperatures were ∼ 10-20 • C higher than present along with reduced latitudinal gradients. Reconstructed seawater oxygen isotope values (δ 18 O w) of −1.5 ‰ to 0.5 ‰ VSMOW and of −5 ‰ to −2.5 ‰ VS-MOW at middle and polar paleolatitudes, respectively, point to a significant freshwater contribution in Arctic regions. These data highlight the risk of assuming the same δ 18 O sw value for δ 18 O-derived temperature from different oceanic regions. These findings provide critical new constraints for model simulations of Jurassic temperatures and δ 18 O sw values and suggest that high climate sensitivity has been a hallmark of greenhouse climates for at least 180 Myr. |
| Document Type: |
article in journal/newspaper |
| Language: |
English |
| DOI: |
10.5194/cp-18-435-2022 |
| Availability: |
https://hal.science/hal-03607369; https://hal.science/hal-03607369v1/document; https://hal.science/hal-03607369v1/file/cp-18-435-2022.pdf; https://doi.org/10.5194/cp-18-435-2022 |
| Rights: |
https://about.hal.science/hal-authorisation-v1/ ; info:eu-repo/semantics/OpenAccess |
| Accession Number: |
edsbas.E1C92ADD |
| Database: |
BASE |