Effective representation of surface-atmosphere fluxes above heterogeneous sea-ice cover for use in climate models (A04#)

• Subject Area: Atmospheric Science
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 268020496

Sea-ice cover significantly influences the Arctic climate and displays heterogeneous patterns, particularly in the marginal ice zone (MIZ). Earth System Models (ESMs) represent this heterogeneity as ice fractions, but this approach fails to capture complex interactions between the surface and atmosphere, including secondary circulations driven by thermal contrasts between sea-ice and open water. The project aims to develop parameterizations for energy, temperature, and moisture fluxes in coarse-resolution ESMs, addressing the lack of representation for small-scale sea-ice variations. Utilizing data from the MOSAiC experiment, the project will explore metrics for accurately modeling the atmospheric boundary layer above heterogeneous sea ice. Ultimately, the goal is to improve the representation of surface-atmosphere exchanges and analyze the implications of increasing lead prevalence due to Arctic warming on the lapse-rate feedback.

• DFG Programme: CRC/Transregios
• Subproject of: TRR 172: ArctiC Amplification: Climate Relevant Atmospheric and SurfaCe Processes, and Feedback Mechanisms (AC)3
• Applicant Institution: Universität Leipzig
• Project Head: Professorin Dr. Nikki Vercauteren, since 1/2025