Logo Universitat Bremen
Page path:

Rethinking the role of the seafloor in ocean chemistry and long-term climate

May 3, 2021, 1:15 pm
MARUM Research Seminar
via Zoom

Ann Dunlea

Department of Marine Chemistry & Geochemistry, Woods Hole Oceanographic Institution, USA

Dur­ing the lim­ited mode of op­er­a­tion due to corona, the lec­tures are held vir­tu­ally via Zoom. Please re­gister by con­tact­ing Maximilian Vahlenkamp ([Bitte aktivieren Sie Javascript]) to re­ceive the ac­cess link.

What controls the long-term trajectory of Earth’s climate and ocean chemistry? How do marine sediments regulate – and bear witness to – these changes? My research investigates the diverse and dynamic subseafloor geochemical processes actively interacting with the ocean and long-term changes in climate. In this talk, I will present a hypothesis that invokes changes in reverse weathering on the seafloor to explain the increase in seawater Mg/Ca and global cooling observed over the past 50 million years. This hypothesis inverts the prevailing hypothesis and abundant models that require an increase in silicate weathering as the driver of many elemental and isotopic trends over the Cenozoic. Ongoing work investigating Cenozoic changes in the cycling of iron, an important micronutrient, will also be discussed.

Ann Dunlea
Ann Dunlea