Climate interactions
Air-sea interactions
[Stephan Juricke, Nils Hutter, Torge Martin, Simon Schäfers, René Schubert]
An important aspect of the climate system is the interaction of different climate components at their interfaces. Atmosphere and ocean exchange heat, freshwater and momentum, driven by the large scale circulation and small scale process both on the oceanic and atmospheric side. We investigate the interactions between these two climate components, especially for turbulent oceanic processes, and their consequences for the Earth system from daily to decadal timescales. This knowledge is then used to improve the coupling of atmosphere and ocean in complex climate models.
Sea ice
[Nils Hutter, Stephan Juricke, Torge Martin]
In polar regions, sea ice regulates the exchange of momentum and heat between the atmosphere and the ocean. This interaction is strongly influenced by small-scale features of the ice, such as floe sizes, open water areas known as leads, and pressure ridges formed by piled-up ice. Our research focuses on developing numerical or data-driven modeling approaches to better represent these fine-scale structures. By creating new parameterizations and evaluation tools based on observational data, we aim to improve the representation of the polar oceans in our coupled climate simulations.
Interaction between surface winds and sea ice in high-resolution (1km) lead-resolving sea ice simulations.
Ice-ocean interaction
Accelerating mass loss from Greenland and Antarctic ice sheets under global warming results not only in global sea-level rise but also affects the ocean circulation, water mass transformation and regional climate conditions. By running meltwater-release experiments in ocean and coupled climate models we are able to quantify the impact of the melting ice sheets on ocean hydrography and circulation with subsequent impacts on AMOC weakening and regional sea level changes. We also contribute to international model intercomparison studies facilitating the improvement of climate projections, such as SOFIA.
Biogeochemistry
The ocean takes up a substantial amount of heat, carbon and oxygen and is thus pivotal in mitigating human-induced climate change. The interaction between wind, ocean circulation and sea ice, modulated by mesoscale eddies, regulates the vigorous exchange of heat and carbon with the atmosphere. In our group, we developed a hierarchy of global ocean biogeochemistry models at increasing horizontal resolution to gain a mechanistic understanding of the effects of climate variability and long-term climate changes on ocean heat, carbon and oxygen patterns. These models can be used at a high-resolution to investigate the role of small-scale processes for air-sea carbon exchanges and biogeochemistry.
