Changes in the high latitude Southern Hemisphere through the Eocene-Oligocene Transition: a model-data comparison

• DOI: 10.5194/cp-2019-112
• Publication Date: 2019-09-06T13:27:31Z
• Authors: Alan T. Kennedy-A...; Daniel J. Lunt; Paul J. Valdes; Jean-Baptiste Ladant; Joost Frieling; Vittoria Lauretano
• Keywords: Proxy (statistics); Antarctic ice sheet; Global temperature

Abstract. Global and regional climate changed dramatically with the expansion of Antarctic Ice sheet at Eocene-Oligocene Transition (EOT). These large-scale changes are generally linked to declining atmospheric pCO2 levels and/or in Southern Ocean gateways such as Drake Passage around this time. To better understand Hemisphere climatic impact glaciation on Earth’s oceans atmosphere EOT, we compiled a database sea land surface temperature reconstructions from range proxy records compared series fully-coupled model simulations. Regional patterns show that cooling across EOT was less high latitudes greater mid-latitudes. Climate simulations have some issues capturing zonal mean latitudinal profiles shown by data, but certain do moderate-good performance recreating data. When taking into account absolute before after well change it, closed or an opening perform poorly, whereas drop combination ice growth better. This provides further support previous research more likely been driver changes, opposed Passage.