Lennart Ramme

Department Climate Variability
Group Director's Research Group (CVR)
Position Postdoc
phone +49 40 41173-162
Email lennart.ramme@mpimet.mpg.de
Room B 216

Research Interests

In my research, I focus on the ocean's role in the global carbon cycle and the climate, investigating time scales from decades to millenia, over which the ocean is the dominant driver of the dynamics within the Earth system. The main tools I use are complex Earth system models like ICON-ESM and MPI-ESM, often in combination with idealized box models, which are helpful to understand individual processes within the system.

During my PhD, I studied these aspects in the context of the Marinoan snowball Earth and the supergreenhouse climate in its aftermath. One of the main outcomes of this work was the quantification of how the ocean responds to excessive amounts of atmospheric CO2 in a scenario of rapid warming during the deglaciation of a snowball Earth - in some ways an extreme version of modern climate change.

Currently, I am a post-doctoral researcher within the Horizon-EU project WorldTrans - Transparent Assessments for Real People. Here, I am looking into the evolution of the ocean carbon uptake in future scenarios of anthropogenic climate change, especially focusing on those scenarios that apply negative carbon emissions to mitigate climate change (like SSP1-1.9 and SSP5-3.4-over). Furthermore, as part of my current position, I am helping in the development of a climate module in the new system dynamcis-based integrated assessment model FRIDA.

ORCID: 0000-0002-8307-2493          Google Scholar          GitHub

More Information

Research Highlights

In my Phd Thesis, I have shown that the ocean plays a major role in the aftermath of the Marinoan snowball Earth. It's dynamic circulation removes any freshwater stratification within a few thousand years. At the same time, the ocean's chemical composition determines the evolution of the supergreenhouse climate, with possible scenarios ranging from a rapid decline to an intensification of the extreme greenhouse conditions.