Date: Wednesday, January 12, 2022
Time: 03:30 pm
Sponsored / Hosted by
Saewung Kim

Department Seminar: Patrick Rafter

Wednesday, January 12, 2022 | 03:30 pm | Zoom
Patrick Rafter
Assistant Project Scientist
Event Details

Title: How “old” was the deep-sea during the last ice age?: Deep-sea circulation, ventilation, carbon storage, and their response to global climate change

Abstract: Although generally accepted, fundamental aspects of the ocean’s role in adjusting atmospheric CO2 before and after the Last Glacial Maximum (LGM) are still debated, including the link between deep-sea ventilation and changes in global ocean overturning. Here I synthesize marine fossil radiocarbon 14C/C measurements—a tracer uniquely sensitive to ocean ventilation—to assess the collective changes in Atlantic, Southern, and Pacific ventilation and circulation since the LGM. I find that an apparently global reduction in LGM deep-sea ventilation persisted alongside an inversion of modern Pacific ventilation. Both ventilation anomalies simultaneously reorganize to modern values early into the deglacial warming. These deep-sea ventilation anomalies provide compelling evidence for a unique glacial ocean overturning that reorganizes to an interglacial configuration, contributing to glacial carbon storage and deglacial release.

The Department of Earth System Science acknowledges our presence on the ancestral and unceded territory of the Acjachemen and Tongva peoples, who still hold strong cultural, spiritual and physical ties to this region.