Constraining carbon input for early-middle Eocene 'hyperthermals'
Abstract
The past ten years have witnessed the continuing discovery of short-lived warming events (‘hyperthermals’) smaller in size and shorter in duration than the Paleocene-Eocene Thermal Maximum (PETM). For example, a 2.4 Myr-long benthic foraminiferal stable isotope record from Demerara Rise has revealed the occurrence of multiple short-lived ‘hyperthermals’ across the early to middle Eocene transition (47.6 to 50 Myr ago). While the PETM is widely attributed to a massive injection of carbon into the oceans-atmosphere from a buried, sedimentary source, the size, duration, and shape of these less-extreme events suggests that their genesis may not require the release of sedimentary-sourced carbon. Instead, redistribution of carbon from readily exchangeable surficial carbon reservoirs could provide a source consistent with the magnitude and shape of these events. Here we use GENIE (Gride Enabled Integrated Earth system model) to evaluate how details of the shape and magnitude of these observed isotopic excursions in both bulk and benthic records relate to the source and quantity of carbon input. In particular, we test competing mechanisms and carbon sources to explain the relatively rapid recovery of these events.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2010
- Bibcode:
- 2010AGUFMPP23B1749K
- Keywords:
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- 4901 PALEOCEANOGRAPHY / Abrupt/rapid climate change;
- 4912 PALEOCEANOGRAPHY / Biogeochemical cycles;
- processes;
- and modeling