Modelling evidence for late Eocene Antarctic glaciations
In: Earth and Planetary Science Letters. Elsevier: Amsterdam. ISSN 0012-821X; e-ISSN 1385-013X, meer
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| Author keywords |
Antarctica; late Eocene; ice sheets; Eocene-Oligocene transition; emulator |
| Abstract |
It is generally believed that a large scale Antarctic ice sheet formed at the Eocene-Oligocene transition (34.44-33.65 Ma). However, oxygen isotope excursions during the late Eocene (38-34 Ma) and geomorphic evidence of glacial erosion suggest that there were ephemeral continental scale glaciations before the Oi-1 event. Here, we investigate the Antarctic ice sheet evolution over a multi-million year timescale during the late Eocene up to the early Oligocene with the most recent estimates of carbon dioxide evolution over this time period and different bedrock elevation reconstructions. A novel ice sheet-climate modelling approach is applied where the Antarctic ice sheet model VUB-AISMPALEO is coupled to the emulated climate from HadSM3 using the coupler CLISEMv1.0. Our modelling results show that short-lived continental scale Antarctic glaciation might have occurred during the late Eocene when austral summer insolation reached a minimum in a narrow range of carbon dioxide concentrations. The Antarctic ice sheet first reached the coast in Prydz Bay and later in the Weddell Sea region, supporting the glaciomarine sediments dated prior to the EOT. |
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