HR: 09:05h
AN: PP31E-05    [Abstracts]
TI: The Influence of Sea-Level Rise on Atmospheric CO₂ Concentration Over the Last Deglacial Transition
AU: * Rippeth, T P
EM: t.p.rippeth@bangor.ac.uk
AF: University of Wales Bangor, School of Ocean Sciences College of Natural Sciences Menai Bridge, Angelesey, LL59 5AB, United Kingdom
AU: Scourse, J D
EM: j.d.scourse@bangor.ac.uk
AF: University of Wales Bangor, School of Ocean Sciences College of Natural Sciences Menai Bridge, Angelesey, LL59 5AB, United Kingdom
AU: Uehara, K
EM: uehara@riam.kyushu-u.ac.jp
AF: Kyushu University, Research Institute for Applied Mechanics, Kyushu University, Fukuoka, 816-8580, Japan
AU: McKeown, S
EM: stephdmckeown@yahoo.com
AF: University of Wales Bangor, School of Ocean Sciences College of Natural Sciences Menai Bridge, Angelesey, LL59 5AB, United Kingdom
AB: Although shelf seas account for only 7% of the oceanic surface area, they play a key role in the global carbon cycle, linking the terrestrial, atmospheric and oceanic carbon pools. Recent observations suggest that whilst tropical shelf seas act as major sources of atmospheric CO₂, temperate and polar shelf seas are significant sinks. Here we provide the first global assessment of the impact of the flooding of the continental shelves by rising sea level on atmospheric pCO₂. We combine reconstructions of shelf palaeogeography, bathymetry and tides, with contemporary estimates of seasonally averaged shelf sea – atmosphere CO₂ exchange to demonstrate the role of the expanding shelf seas in regulating atmospheric CO₂ over the past 21,000 years. This period covers the last deglacial transition following the Last Glacial Maximum (LGM). We show that the relative growth of these different regimes provides a mechanism which can explain the direction, rate and timing of a number of previously unexplained transitions in the atmospheric pCO₂ record derived from ice-core measurements. The results demonstrate the influence of rising sea level on atmospheric pCO₂ and the important role of the contemporary shelf seas within the global carbon cycle.
DE: 3344 Paleoclimatology (0473, 4900)
DE: 4900 PALEOCEANOGRAPHY (0473, 3344)
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2007 Fall Meeting