Journey Through Ice: Navigating Air and Dye Channels

My research focuses on how contaminants in aqueous solutions affect the freezing process and ice-surface interactions. Pure ice tends to hold onto surfaces very strongly. Yet the smallest amounts of contaminants seem to cause the ice to slide off with the slightest applied force. Even more peculiar, there is a solute-enriched liquid layer that remains once the ice is pushed away, even for low weight-percentages of contaminants that should otherwise be frozen in the bulk ice. There must be some kind of mechanism that collects contaminants in the bulk ice and then channels them downwards towards the supercooled surface where it pools as an unfrozen aqueous liquid. To investigate these channels, we looked through a column of ice that was contaminated with dye. A camera with a macro lens moves its view at 20 microns per second through the ice, where we can see large air channels that formed from trapped air bubbles which diffused out during the freezing process. We also see thin strands and speckles of pink dye as the contaminants migrate through the ice and form small high-concentration pockets, which seem to burrow downwards towards the surface.