Frost flowers in the laboratory: Growth, characteristics, aerosol, and the underlying sea ice

• Published in: Journal of Geophysical Research
• Main Authors: Roscoe, H.K., Brooks, B., Jackson, A.V., Smith, M.H., Walker, S.J., Obbard, R.W., Wolff, E.W.
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Geophysical Union 2011
• Subjects: Marine Sciences; Glaciology; Atmospheric Sciences; Chemistry; Arctic; Sea ice
• Online Access: http://nora.nerc.ac.uk/id/eprint/14687/; https://nora.nerc.ac.uk/id/eprint/14687/1/jgrd16902.pdf; https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2010JD015144

In the laboratory, we have investigated the growth and composition of frost flowers. Their ionic composition has shown little difference from those of field measurements. Young frost flowers grown on sea ice are saline, leading us to speculate that wicking occurs continually during their growth on sea ice. The surface area of frost flowers is only a little larger than the area of ice underneath, consistent with recent field measurements from the Arctic. Time-lapse photography has allowed us to observe the extreme mobility of freshly forming sea ice, at the stage at which the mush has become rather solid, and continuing while the flowers grow. This mobility results in new brine being expelled to the surface, which therefore remains wet. During various stages of frost flower growth, we observed their freshly formed dendritic parts rapidly diminishing in size after contacting the surface, consistent with repeated wicking. Frost flowers proved to be very stable in the presence of wind, such that no aerosol was observed when wind was blown across them in the laboratory chamber. This is consistent with recent field observations of frost flowers coexisting with wind-blown snow