The effect of the Central American Seaway on ocean oxygen

durch Dr. Médéric St-Pierre (FB2/BM)

Mittwoch 15.10.2025, 13:15 → 14:30 Europe/Berlin

8A-002 - Hörsaal Ostufer / Lecture Hall East (GEOMAR - Standort Ostufer / GEOMAR - East Shore)

Abstract:

The Miocene is a good proxy for today’s climate because it is a warm period where CO₂ concentrations were estimated to be around 300 to 600 ppm. It was also a key time in Earth’s history, as continents and oceans were shifting into their modern positions. One of the most important features of this period was the Open Central American Seaway (CAS), which connected the Pacific and Atlantic Oceans. As the CAS started to gradually close towards the end of the Miocene, it changed how water, heat, and nutrients moved between the two oceans. These changes had major effects on global ocean circulation and on the amount of oxygen available in different parts of the global ocean. Here, we study primarily the influence of the CAS on ocean circulation and oxygen and find that opening the CAS with modern bathymetry leads to more oxygen in the Pacific Ocean, less oxygen in the Atlantic Ocean, and important changes to the Atlantic Meridional Overturning Circulation.