Project Details
Projekt
Theoretical and experimental investigation of Arctic ice formation during the summer months employing metallic model alloys in application to climate change
Subject Area
Thermodynamics and Kinetics as well as Properties of Phases and Microstructure of Materials
Term
since 2025
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 556975451
The project aims the combination of modern experimental techniques and mathematical modeling describing phase transformations to meet nowadays challenges in understanding environmental/climate development. The project is dedicated to studying the formation of Arctic ice during the summer months, namely natural phenomenon of "false bottom" effect, by providing experiments on the re-solidification of semisolid metallic alloys in temperature and concentrations gradients, as well as verifying and extending a previously developed mathematical/physical model of the process from microscale to global climate (budget). The topic is important in terms of climate policy and has been known for a long time, nevertheless, the phenomenon’s underlying mechanisms are still not completely understood. The main reason for the lack in understanding is the limited experimental access. In the frame of the project the existing qualitative models will be expanded and validated with experimental investigations using metallic alloys as a model system. The novel results will help the quantitative understanding of the effect and are highly-evaluated from interdisciplinary point of view, including glaciology and geosciences, and are ultimately significant for the understanding the global climate change landscape. The mechanism of false-bottom formation is based on a slight temperature drop combined with local concentration differences and has not been described in details due to difficulties in field measurements and experimental observations, although it makes a significant contribution to the climate balance. Concentration-induced solidification is a known and partially understood phenomenon in the field of phase transformations of metallic materials. The experimental and theoretical studies on the model alloys will reduce the objective complexity of obtaining and analyzing field data for further model development and verification. The combination of experiment and modeling will enable complex parameter study and analysis of structure formation as well as process properties using state-of-the-art thermography and electron microscopy to identify the critical factors affecting the global ecosystem heat balance. The conditions for ice layer formation will be studied experimentally, then the experimental results will be incorporated into mathematical/physical modeling considering the theory of the moving boundaries. The original natural system model will be improved and verified on specially developed concentration profiles in metallic samples that mimic the natural ice/melt water/ocean water system. Transfer of the enhanced model to geoscience systems with additional verification against available field data, including recent field MOSAiC experiment, will advance current research and enable innovative applications related to global problems such as climate change.
DFG Programme
Research Grants
Co-Investigators
Professor Dr. Florian Kargl; Dr. Elke Sondermann
