HR: 10:50h
AN: PP52B-03 INVITED     [Abstracts]
TI: Extremely High Late Paleocene - Early Eocene Sea Surface Temperatures On The North Pole
AU: * Sluijs, A
EM: A.Sluijs@bio.uu.nl
AF: Laboratory of Palaeobotany and Palynology, Department of Biology, Utrecht University, Budapestlaan 4, Utrecht, 3584 CD Netherlands
AU: Schouten, S
EM: schouten@nioz.nl
AF: Royal Netherlands Institute for Sea Research (NIOZ), Department of Marine Biogeochemistry and Toxicology, PO Box 59, Den Burg, 1790 AB Netherlands
AU: Pagani, M
EM: mark.pagani@yale.edu
AF: Department of Geology and Geophysics Yale University Geophysics Yale University, P.O. Box 208109, New Haven, CT 06520 United States
AU: Brinkhuis, H
EM: H.Brinkhuis@bio.uu.nl
AF: Laboratory of Palaeobotany and Palynology, Department of Biology, Utrecht University, Budapestlaan 4, Utrecht, 3584 CD Netherlands
AU: Sinninghe Damst‚, J
EM: damste@nioz.nl
AF: Royal Netherlands Institute for Sea Research (NIOZ), Department of Marine Biogeochemistry and Toxicology, PO Box 59, Den Burg, 1790 AB Netherlands
AU: Sinninghe Damst‚, J
EM: damste@nioz.nl
AF: Department of Earth Sciences, Utrecht University, Budapestlaan 4, Utrecht, 3584 CD Netherlands
AU: Dickens, G R
EM: jerry@rice.edu
AF: Department of Earth Sciences, Rice University, 6100 Main Street, Houston, TX 77005 United States
AU: Huber, M
EM: huberm@purdue.edu
AF: Earth and Atmospheric Sciences Department and the Purdue Climate Change Research Center, Purdue University, 550 Stadium Mall Drive, West Lafayette, IN 47906 United States
AU: Reichart, G
EM: reichart@geo.uu.nl
AF: Department of Earth Sciences, Utrecht University, Budapestlaan 4, Utrecht, 3584 CD Netherlands
AU: Stein, R
EM: rstein@awi-bremerhaven.de
AF: Alfred-Wegener-Institute for Polar and Marine Research, Columbusstrasse, Bremerhaven, 27568 Germany
AU: Lourens, L J
EM: llourens@geo.uu.nl
AF: Department of Earth Sciences, Utrecht University, Budapestlaan 4, Utrecht, 3584 CD Netherlands
AB: The late Paleocene and early Eocene are characterized by warm global temperatures, likely associated with elevated greenhouse gas concentrations. Superimposed on the long-term warming trend during this inteval, several transient events of widespread extreme warming occurred, associated with massive input of even more greenhouse gases, of which the most extreme happened at the Paleocene-Eocene boundary approximately 55 million years ago. Surface temperature evolution of low- to mid latitudes and also of deep-ocean waters (which are likely derived from surface waters of sub-polar regions) have been reasonably well documented across this Palaeocene-Eocene thermal maximum (PETM). However, to fully assess pole-to-equator gradients and potential polar amplification of greenhouse warming during the PETM, polar records are required. Here we identify the PETM in a recently recovered (Arctic Coring Expedition, IODP Leg 302, August-September 2004) marine sedimentary sequence deposited near the North Pole and examine the pattern of Arctic climate change during this extreme climate anomaly. We show that during the PETM the tropical dinoflagellate Apectodinium inhabited the Arctic Ocean, when (TEX₈₆-derived, in this case likely reflecting summer-) surface temperatures rose from 18°C to over 23°C. Concomitantly, sea level rose and photic zone euxinia developed. Arctic surface temperatures before, during and after the PETM were at least 10°C warmer than predicted by paleoclimate model simulations with 2000 ppmv CO₂. Moreover, our data confirm previously-noted significantly reduced pole-to-equator temperature gradients that cannot be reproduced by the current generation of fully coupled climate models. This suggests that feedback mechanisms that are unimplemented in the models played a crucial role in the polar-amplified warmth of early Paleogene climates, in conjunction with elevated greenhouse gas concentrations. Finally, our results show that the pole-to-equator temperature gradient remained similar during the PETM, suggesting that the mechanism that caused early Paleogene reduced gradients was largely saturated at this event.
DE: 4850 Marine organic chemistry (0470, 1050)
DE: 4901 Abrupt/rapid climate change (1605)
DE: 4928 Global climate models (1626, 3337)
DE: 4948 Paleocene/Eocene thermal maximum
DE: 4952 Palynology
SC: Paleoceanography and Paleoclimatology [PP]
MN: Fall Meeting 2005